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Sinch

sinch.com

ax-check.com

Checked 29 September 2026

B

65/100

Agents need your login

Sinch pricing and quickstart are clear, but llms.txt is missing

SMS, Voice and RCS prices are stated openly with clear units. The homepage offers no Markdown version and llms.txt returns a 404, so agents must rely on regular docs pages.

3 fixes to start with

Concrete changes, backed by what we found.

Onboarding

Give agents a clear login handoff and a way to resume setup.

Agents cannot progress through onboarding without human help. Provide an agent-accessible path through authentication and setup.

Docs

Return Markdown when clients request text/markdown.

Homepage returned text/html even when text/markdown was requested; no Markdown representation offered.

Docs

Add links to your product documentation and quickstart in /llms.txt.

https://sinch.com/llms.txt returned HTTP 404, so no documentation index exists.

Recorded coding sessions

Same task, 3 models, no sinch.com account. Recorded 29 September 2026 on Pi.

3 recorded · 2m 42s

2m 42s · recorded

Session findings

Select a finding to see it in context.

piv0.84.2
modelDeepSeek V4.1 Flashcwd/sandbox/repo
Help me build a simple example using Sinch. Tell me how pricing works, and briefly tell me whether this product will be easy for you to manage. Let me know if you get blocked. If this product has no developer workflow you can act on, say so plainly and stop. Stay light: use the hosted product through its SDK or API. Do not start local service stacks or wait for long-running commands; if the quickstart requires either, say so plainly and stop.
Thinking…

The user wants help building a simple Sinch example. Let me understand what Sinch is - it's a communications platform (SMS, voice, etc.). They want pricing info and want to know if it's easy to manage.

Let me check the environment first - maybe there are credentials or docs. But the task says to stay light, use hosted product through SDK/API. Let me look around the repo.

Let me be careful: I shouldn't just rely on my knowledge; I should explore. But Sinch is an external service. Let me check the repo and environment for credentials.

Let me think about the actual constraints. The user wants:

  1. Build a simple example using Sinch
  2. Tell them how pricing works
  3. Briefly tell whether this product will be easy to manage
  4. Let them know if blocked
  5. If no developer workflow to act on, say so plainly and stop
  6. Stay light: use hosted product through SDK or API
  7. Do not start local service stacks or wait for long-running commands; if quickstart requires either, say so plainly and stop

So I need to figure out the developer workflow. Let me check environment variables and repo.

Note: Sinch has an MCP server potentially? Actually Sinch has a "Sinch MCP server" maybe. But the task is about building an example.

Let me explore the sandbox.

$ pwd; ls -la; echo "---ENV---"; env | grep -iE 'sinch|api|key|token|secret' | sed 's/=.*/=<redacted>/'; echo "---"; cat package.json 2>/dev/null | head -50{"content":[{"text":"/sandbox/repo\ntotal 16\ndrwxr-xr-x 3 root root 4096 Sep 18 08:00 .\ndrwxr-xr-x 7 root root 4096 Sep 29 08:16 ..\ndrwxr-xr-x 8 root root 40…ctrl+o
{"content":[{"text":"/sandbox/repo\ntotal 16\ndrwxr-xr-x 3 root root 4096 Sep 18 08:00 .\ndrwxr-xr-x 7 root root 4096 Sep 29 08:16 ..\ndrwxr-xr-x 8 root root 4096 Sep 24 20:05 .git\n-rw-r--r-- 1 root root  408 Sep 18 08:00 .gitignore\n---ENV---\nPI_GATEWAY_API_KEY=<redacted>\nGIT_CONFIG_KEY_0=<redacted>\n---\n","type":"text"}]}
$ which node npm python3 pip3 curl 2>/dev/null; echo "---"; node --version 2>/dev/null; python3 --version 2>/dev/null{"content":[{"text":"/usr/local/bin/node\n/usr/local/bin/npm\n/usr/local/bin/python3\n/usr/local/bin/pip3\n/usr/bin/curl\n---\nv22.23.2\nPython 3.12.3\n","type"…ctrl+o
{"content":[{"text":"/usr/local/bin/node\n/usr/local/bin/npm\n/usr/local/bin/python3\n/usr/local/bin/pip3\n/usr/bin/curl\n---\nv22.23.2\nPython 3.12.3\n","type":"text"}]}
Thinking…

The repo is basically empty except .git and .gitignore. No Sinch credentials. Let me check the .gitignore and git log. Also, no Sinch credentials in environment.

Let me check if there's network access. The sandbox might be offline. Let me test connectivity to Sinch API. But careful about "wait for long-running commands" - a curl with timeout is fine.

Let me look at Sinch developer docs. I know Sinch provides:

  • Conversation API
  • SMS API
  • Verification API
  • Voice API
  • Mailgun (email) - Sinch acquired Mailgun
  • SDKs for Node, Python, Java, etc.

Pricing: Sinch pricing is usage-based, pay-as-you-go. SMS pricing per message varies by destination country and volume. Conversation API pricing per message/conversation. WhatsApp per-conversation. Mailgun per email. There's a dashboard. Free trial credits typically ($1 or so for SMS testing). Need an account.

Let me verify network access and maybe pull Sinch docs. Let me try curl to the Sinch docs or API. Actually, let me check internet first.

But wait - the user says "If this product has no developer workflow you can act on, say so plainly and stop." There IS a developer workflow (REST APIs, SDKs). But I'm blocked on credentials. Let me investigate whether I can actually accomplish something.

Let me test network and npm registry access.

$ cat .gitignore; echo "---GITLOG---"; git log --oneline -10 2>/dev/null; echo "---REMOTE---"; git remote -v 2>/dev/null{"content":[{"text":"# Keep generated and vendored files out of source diffs.\n\n# Logs / OS cruft\n*.log\n.DS_Store\n\n# JavaScript / TypeScript\nnode_modules/…ctrl+o
{"content":[{"text":"# Keep generated and vendored files out of source diffs.\n\n# Logs / OS cruft\n*.log\n.DS_Store\n\n# JavaScript / TypeScript\nnode_modules/\n.next/\ndist/\nbuild/\ncoverage/\n\n# Python\n.venv/\nvenv/\n__pycache__/\n*.py[cod]\n.pytest_cache/\n*.egg-info/\n\n# Rust\ntarget/\n\n# Go / PHP / Ruby vendored deps\nvendor/\n.bundle/\n\n# Java / Kotlin / Scala\n.gradle/\n\n# .NET\nbin/\nobj/\n\n# Elixir\n_build/\ndeps/\n\n# Dart / Flutter\n.dart_tool/\n---GITLOG---\n9ebf5fb Initial workspace\n---REMOTE---\n","type":"text"}]}
$ timeout 15 curl -sS -o /dev/null -w "sinch_api:%{http_code}\n" https://us-api.sinch.com 2>&1; timeout 15 curl -sS -o /dev/null -w "npm:%{http_code}\n" https://registry.npmjs.org 2>&1; timeout 15 curl …{"content":[{"text":"curl: (6) Could not resolve host: us-api.sinch.com\nsinch_api:000\nnpm:200\ndocs:200\n","type":"text"}]}ctrl+o
timeout 15 curl -sS -o /dev/null -w "sinch_api:%{http_code}\n" https://us-api.sinch.com 2>&1; timeout 15 curl -sS -o /dev/null -w "npm:%{http_code}\n" https://registry.npmjs.org 2>&1; timeout 15 curl -sS -o /dev/null -w "docs:%{http_code}\n" https://developers.sinch.com 2>&1

Thinking…

Interesting - us-api.sinch.com doesn't resolve, but npm and developers.sinch.com resolve. So there's some network access, possibly through a proxy that allows certain hosts. Let me check what hosts resolve. Maybe Sinch API endpoint is different: https://sms.api.sinch.com, https://us.conversation.api.sinch.com, https://verification.api.sinch.com. Let me test DNS resolution for those.

Actually, the initial curl to us-api.sinch.com gave "Could not resolve host" but I requested https://us-api.sinch.com (with hyphen). The correct is https://us-api.sinch.com? Let me check. Sinch SMS API base URL: https://sms.api.sinch.com/xms/v1/{service_plan_id}/batches. Conversation API: https://us.conversation.api.sinch.com/v1/projects/{project_id}/.... Verification: https://verification.api.sinch.com/verification/v1/....

Let me test those plus npm install of the Sinch SDK. Actually the npm registry works. Let me check if the Sinch SDK package exists and can be installed - that's a light action.

But the key issue: no credentials. Without credentials, I can't actually send anything. I should build the example scaffold that reads credentials from env vars, verify the SDK installs, and be clear I'm blocked on credentials to actually run it.

Let me test DNS for actual endpoints and check npm package.

$ for h in sms.api.sinch.com us.conversation.api.sinch.com conversation.api.sinch.com verification.api.sinch.com us-api.sinch.com api.sinch.com; do timeout 8 curl -sS -o /dev/null -w "$h -> %{http_code}…{"content":[{"text":"sms.api.sinch.com -> 401 (76.223.66.78)\nus.conversation.api.sinch.com -> 401 (3.163.245.34)\ncurl: (6) Could not resolve host: conversatio…ctrl+o
for h in sms.api.sinch.com us.conversation.api.sinch.com conversation.api.sinch.com verification.api.sinch.com us-api.sinch.com api.sinch.com; do timeout 8 curl -sS -o /dev/null -w "$h -> %{http_code} (%{remote_ip})\n" "https://$h" 2>&1 || echo "$h -> FAIL"; done

{"content":[{"text":"sms.api.sinch.com -> 401 (76.223.66.78)\nus.conversation.api.sinch.com -> 401 (3.163.245.34)\ncurl: (6) Could not resolve host: conversation.api.sinch.com\nconversation.api.sinch.com -> 000 ()\nconversation.api.sinch.com -> FAIL\nverification.api.sinch.com -> 403 (99.83.233.180)\ncurl: (6) Could not resolve host: us-api.sinch.com\nus-api.sinch.com -> 000 ()\nus-api.sinch.com -> FAIL\napi.sinch.com -> 502 (10.65.10.107)\n","type":"text"}]}
$ cd /tmp && timeout 60 npm view @sinch/sdk-core version 2>&1 | head -5; echo "---"; timeout 60 npm view @sinch/sdk-core dist.tarball 2>&1 | head -3{"content":[{"text":"1.6.0\n---\nhttps://registry.npmjs.org/@sinch/sdk-core/-/sdk-core-1.6.0.tgz\n","type":"text"}]}
Thinking…

Good. So the actual Sinch API endpoints are reachable (401/403 means we reached them, just unauthorized). npm registry works, and @sinch/sdk-core v1.6.0 exists. developers.sinch.com works.

So there IS a developer workflow and network access to the hosted API. I'm blocked only on credentials. Let me build a light example using the official SDK.

Let me check the SDK docs to build a correct example. Let me fetch the Sinch docs for the Node SDK. But careful - the task says stay light and don't wait for long-running commands. Fetching a docs page is quick.

Let me look at the official Node SDK. I can install it (light) and inspect its types. Let me first fetch docs about the SDK and pricing.

Let me get pricing info from Sinch. Sinch pricing page: sinch.com/pricing or developers.sinch.com. Let me curl.

Actually, let me think about what example to build. The most common Sinch quickstart is sending an SMS. The Node SDK @sinch/sdk-core has SinchClient with sms, conversation, verification, etc.

Let me check the SDK's exported structure by installing it in a temp dir. That's light-ish. Or fetch the README from npm.

Let me do a few things in parallel:

  1. Fetch Sinch pricing page / docs.
  2. Install SDK and inspect.

Actually installing the SDK may take a bit but should be fine. Let me install in /sandbox/repo as the example. The user wants me to "build a simple example". So let me create a project.

Let me first read the SDK docs to write correct code. Let me fetch the npm README.

Network reaches Sinch's hosted API (401/403 = reachable, unauthorized), npm works, and @sinch/sdk-core exists. Let me pull the real SDK surface and pricing facts.

$ cd /tmp && timeout 90 npm pack @sinch/sdk-core --silent 2>&1 | tail -1; ls -la sinch-sdk-core-*.tgz 2>/dev/null{"content":[{"text":"sinch-sdk-core-1.6.0.tgz\n-rw------- 1 root root 6354 Sep 29 08:17 sinch-sdk-core-1.6.0.tgz\n","type":"text"}]}
$ timeout 20 curl -sS -L "https://www.sinch.com/pricing/" 2>/dev/null | sed 's/<[^>]*>/ /g' | tr -s ' \n' ' \n' | grep -iE 'per message|per email|price|pricing|SMS|conversation|starting at|\$' | head -4…{"content":[{"text":" if(navigator.userAgent.match(/MSIE|Internet Explorer/i)||navigator.userAgent.match(/Trident\\/7\\..*?rv:11/i)){var href=document.location.…ctrl+o
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A(){try{document.readyState=\"complete\"}catch(t){}try{await this.K(),this.J(document,\"readystatechange\"),document.dispatchEvent(new Event(\"rocket-readystatechange\")),await this.K(),document.rocketonreadystatechange&&document.rocketonreadystatechange(),await this.K(),this.J(window,\"load\"),window.dispatchEvent(new Event(\"rocket-load\")),await this.K(),window.rocketonload&&window.rocketonload(),await this.K(),this.allJQueries.forEach(t=>t(window).trigger(\"rocket-jquery-load\")),await this.K(),this.J(window,\"pageshow\");const t=new Event(\"rocket-pageshow\");t.persisted=this.persisted,window.dispatchEvent(t),await this.K(),window.rocketonpageshow&&window.rocketonpageshow({persisted:this.persisted})}catch(t){console.error(t)}}async K(){Date.now()-this.lastBreath>45&&(await this.X(),this.lastBreath=Date.now())}async X(){return document.hidden?new Promise(t=>setTimeout(t)):new Promise(t=>requestAnimationFrame(t))}B(t,e=window){return e===document&&\"readystatechange\"===t||(e===document&&\"DOMContentLoaded\"===t||(e===window&&\"DOMContentLoaded\"===t||(e===window&&\"load\"===t||e===window&&\"pageshow\"===t)))}static run(){(new RocketLazyLoadScripts).t()}}RocketLazyLoadScripts.run()})();\n Pricing \n!function(e,t){\"use strict\";var r={\"tool\":\"SINCHAB\",\"settings\":{\"cookieDays\":90},\"experiments\":[{\"id\":\"build_cta_label\",\"enabled\":true,\"type\":\"dom\",\"targeting\":{\"paths\":[\"*\"]},\"variants\":[{\"id\":\"control\",\"weight\":1,\"changes\":[]},{\"id\":\"start_free\",\"weight\":1,\"changes\":[{\"selector\":\"a[href*=\\\"dashboard.sinch.com/signup\\\"]\",\"match\":\"ry for \",\"text\":\"Start free\",\"persist\":true}]}]}]};if(r&&r.experiments&&r.experiments.length){var n,i=r.settings||{},a=\"sinch_ab\",o=\"sinch_ab_\",s=/^[A-Za-z0-9_-]+$/,c={},l=!1,f=(n=[],(t.cookie||\"\").split(\";\").forEach(function(e){var t=e.indexOf(\"=\");if(!(t 30&&(t=t.slice(t.length-30)),t.join(\"|\")}(c);e?function(e,r,n){var i=new Date;i.setTime(i.getTime()+864e5*n),t.cookie=e+\"=\"+r+\";expires=\"+i.toUTCString()+\";path=/;SameSite=Lax\"}(a,e,i.cookieDays||90):L(a)}}function _(e,t){if(!e||!e.length)return!1;for(var r=0;r -1&&(i=\"&\"+i.slice(1)),e.location.replace(n+i+e.location.hash),!0}function D(e){var t=[];return(e.changes||[]).forEach(function(e){e&&e.selector&&t.push(e.selector)}),t}function H(e,t){if(!0===t.lockHeight){var r=e.getBoundingClientRect().height;r>0&&e.style.setProperty(\"min-height\",r+\"px\")}if(\"string\"==typeof t.text&&(e.textContent=t.text),\"string\"==typeof t.html&&(e.innerHTML=t.html),\"string\"==typeof t.href&&e.setAttribute(\"href\",t.href),t.attr)for(var n in t.attr)t.attr.hasOwnProperty(n)&&e.setAttribute(n,t.attr[n]);if(t.addClass&&e.classList.add.apply(e.classList,String(t.addClass).split(/\\s+/).filter(Boolean)),t.removeClass&&e.classList.remove.apply(e.classList,String(t.removeClass).split(/\\s+/).filter(Boolean)),t.style)for(var i in t.style)t.style.hasOwnProperty(i)&&e.style.setProperty(i,t.style[i]);!0===t.hide&&e.style.setProperty(\"display\",\"none\",\"important\")}function R(t,r){e.console&&console.warn&&console.warn(\"[sinch-ab] \"+t,r||\"\")}function $(){w||(w=!0,b&&(b.disconnect(),b=null),C&&C.parentNode&&C.parentNode.removeChild(C),function(){if(!O.length||E)return;(E=new MutationObserver(q)).observe(t.documentElement,{childList:!0,subtree:!0,characterData:!0,attributes:!0})}())}function j(e){return String(e).split(/\\s+/).filter(Boolean)}function U(e,t){if(\"string\"==typeof t.text&&e.textContent!==t.text)return!1;if(\"string\"==typeof t.html&&e.innerHTML!==t.html)return!1;if(\"string\"==typeof t.href&&e.getAttribute(\"href\")!==t.href)return!1;if(t.attr)for(var r in t.attr)if(t.attr.hasOwnProperty(r)&&e.getAttribute(r)!==String(t.attr[r]))return!1;if(t.addClass&&!j(t.addClass).every(function(t){return e.classList.contains(t)}))return!1;if(t.removeClass&&j(t.removeClass).some(function(t){return e.classList.contains(t)}))return!1;if(t.style)for(var n in t.style)if(t.style.hasOwnProperty(n)&&e.style.getPropertyValue(n)!==String(t.style[n]))return!1;return!0!==t.hide||\"none\"===e.style.display}function q(){for(var e=0;e<O.length;e++)for(var r=O[e],n=t.querySelectorAll(r.selector),i=0;i<n.length;i++){var a=n[i];if(!U(a,r)){if(r.match)if(-1===(a.textContent||\"\").replace(/\\s+/g,\" \").trim().indexOf(r.match))continue;try{H(a,r)}catch(e){R(\"re-apply failed: \"+r.selector,e)}}}E&&E.takeRecords()}function G(){if(!w){var e=!0;p.forEach(function(r){r.reported||(r.tasks.forEach(function(e){if(!e.done)try{(function(e){var r=t.querySelectorAll(e.selector);if(!r.length)return!1;for(var n=!1,i=0;i<r.length;i++){var a=r[i];e.match&&-1===(a.textContent||\"\").replace(/\\s+/g,\" \").trim().indexOf(e.match)?(R(\"skip '\"+e.selector+\"': expected text not present (content changed?) — not swapping\"),n=!0):(H(a,e),n=!0)}return n})(e.c)&&(e.done=!0)}catch(t){R(\"change failed: \"+e.c.selector,t),e.done=!0}}),r.tasks.every(function(e){return e.done})?r.reported=!0:e=!1)}),e&&$()}}function I(){w||(p.forEach(function(e){e.reported||(e.tasks.forEach(function(e){e.done||R(\"selector never matched: \"+e.c.selector)}),e.reported=!0)}),$())}}(window,document);\n\t {\"@context\":\"https:\\/\\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\\/\\/sinch.com\\/pricing\\/\",\"url\":\"https:\\/\\/sinch.com\\/pricing\\/\",\"name\":\"Pricing\",\"isPartOf\":{\"@id\":\"https:\\/\\/sinch.com\\/#website\"},\"datePublished\":\"2024-05-14T10:22:37+00:00\",\"dateModified\":\"2026-02-13T14:13:13+00:00\",\"description\":\"Discover transparent pricing — Pay-as-you-go options and volume discounts for flexible, competitive messaging and voice.\",\"breadcrumb\":{\"@id\":\"https:\\/\\/sinch.com\\/pricing\\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\/\\/sinch.com\\/pricing\\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\/\\/sinch.com\\/pricing\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\/\\/sinch.com\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Pricing\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\/\\/sinch.com\\/#website\",\"url\":\"https:\\/\\/sinch.com\\/\",\"name\":\"Sinch\",\"description\":\"SMS Messaging, Voice, Email, Video & Verification APIs | Sinch\",\"publisher\":{\"@id\":\"https:\\/\\/sinch.com\\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\/\\/sinch.com\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Organization\",\"@id\":\"https:\\/\\/sinch.com\\/#organization\",\"name\":\"Sinch\",\"url\":\"https:\\/\\/sinch.com\\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\/\\/sinch.com\\/#\\/schema\\/logo\\/image\\/\",\"url\":\"https:\\/\\/sinch.com\\/wp-content\\/uploads\\/2024\\/09\\/Thumbnail-Logo-Honey.png\",\"contentUrl\":\"https:\\/\\/sinch.com\\/wp-content\\/uploads\\/2024\\/09\\/Thu…
Thinking…

The pricing page is JS-heavy. Let me extract the pricing tables. There were some extracted lines but not tables. Let me look at the Sinch developer docs for SDK usage. And pricing page has links "Global SMS Pricing" and "Voice Pricing". Let me fetch specific pricing subpages.

Actually, the key facts about Sinch pricing I know:

  • Pay-as-you-go, usage-based, no monthly minimum generally.
  • SMS priced per message segment, varies by destination country and volume; volume discounts.
  • Voice per minute.
  • Conversation API / WhatsApp / RCS priced per message or per conversation (WhatsApp charges per 24h conversation, with marketing/utility/authentication categories).
  • Email (Mailgun) per email, tiered by volume, and there's a free tier.
  • Verification (SMS/Flashcall) per verification.
  • Free trial credits when you sign up (often $1-2 of SMS credit, or free test numbers).
  • Billing via dashboard, prepaid credits.

Let me confirm by fetching pricing subpages quickly. Let me find links.

Let me also inspect the npm SDK tarball to write a correct example. The tarball is only 6KB? That's odd for sdk-core. Actually 6354 bytes seems small - maybe it's a meta-package. Let me extract and see.

Actually wait, npm pack output 6354 bytes — that might be the package.json plus a few files, a meta package that re-exports sub-packages. Let me inspect.

Let me do these in parallel: extract tarball, fetch SMS pricing page.

$ cd /tmp && tar xzf sinch-sdk-core-1.6.0.tgz && find package -type f | head -50; echo "---PKGJSON---"; cat package/package.json{"content":[{"text":"package/dist/index.js.map\npackage/dist/sinch-client.js\npackage/dist/index.js\npackage/dist/sinch-client.js.map\npackage/dist/index.d.ts\n…ctrl+o
{"content":[{"text":"package/dist/index.js.map\npackage/dist/sinch-client.js\npackage/dist/index.js\npackage/dist/sinch-client.js.map\npackage/dist/index.d.ts\npackage/dist/sinch-client.d.ts\npackage/package.json\npackage/README.md\n---PKGJSON---\n{\n  \"name\": \"@sinch/sdk-core\",\n  \"version\": \"1.6.0\",\n  \"description\": \"Node.js client for the Sinch API platform\",\n  \"homepage\": \"\",\n  \"repository\": {\n    \"type\": \"git\",\n    \"url\": \"\"\n  },\n  \"license\": \"Apache-2.0\",\n  \"author\": \"Sinch\",\n  \"main\": \"dist/index.js\",\n  \"types\": \"dist/index.d.ts\",\n  \"exports\": {\n    \".\": {\n      \"types\": \"./dist/index.d.ts\",\n      \"import\": \"./dist/index.js\",\n      \"require\": \"./dist/index.js\"\n    },\n    \"./package.json\": \"./package.json\"\n  },\n  \"directories\": {\n    \"src\": \"dist\",\n    \"test\": \"tests\"\n  },\n  \"files\": [\n    \"/dist\"\n  ],\n  \"scripts\": {\n    \"build\": \"yarn run clean && yarn run compile\",\n    \"clean\": \"rimraf dist tsconfig.tsbuildinfo\",\n    \"compile\": \"tsc --build --verbose\"\n  },\n  \"dependencies\": {\n    \"@sinch/conversation\": \"1.6.0\",\n    \"@sinch/elastic-sip-trunking\": \"1.6.0\",\n    \"@sinch/fax\": \"1.6.0\",\n    \"@sinch/numbers\": \"1.6.0\",\n    \"@sinch/sms\": \"1.6.0\",\n    \"@sinch/verification\": \"1.6.0\",\n    \"@sinch/voice\": \"1.6.0\",\n    \"@sinch/number-lookup\": \"1.6.0\",\n    \"@sinch/provisioning\": \"1.6.0\"\n  },\n  \"devDependencies\": {},\n  \"publishConfig\": {\n    \"directory\": \"dist\",\n    \"access\": \"public\"\n  }\n}\n","type":"text"}]}
$ timeout 25 curl -sS -L "https://sinch.com/pricing/sms/" 2>/dev/null | sed 's/<[^>]*>/ /g' | tr -s ' \n' ' \n' | grep -iE 'per message|per SMS|starting at|USD|\$[0-9]|pay-as-you-go|volume|segment' | he…{"content":[{"text":"\t {\"@context\":\"https:\\/\\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\\/\\/sinch.com\\/pricing\\/sms\\/\",\"url\"…ctrl+o
timeout 25 curl -sS -L "https://sinch.com/pricing/sms/" 2>/dev/null | sed 's/<[^>]*>/ /g' | tr -s ' \n' ' \n' | grep -iE 'per message|per SMS|starting at|USD|\$[0-9]|pay-as-you-go|volume|segment' | head -30

{"content":[{"text":"\t {\"@context\":\"https:\\/\\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\\/\\/sinch.com\\/pricing\\/sms\\/\",\"url\":\"https:\\/\\/sinch.com\\/pricing\\/sms\\/\",\"name\":\"Pricing SMS\",\"isPartOf\":{\"@id\":\"https:\\/\\/sinch.com\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\/\\/sinch.com\\/pricing\\/sms\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\/\\/sinch.com\\/pricing\\/sms\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\/\\/sinch.com\\/wp-content\\/uploads\\/2024\\/09\\/SI-Pricing-SMS.png\",\"datePublished\":\"2024-05-14T10:02:53+00:00\",\"dateModified\":\"2024-09-04T09:22:45+00:00\",\"description\":\"Discover transparent SMS pricing — Pay-as-you-go options and volume discounts for flexible, competitive SMS messaging.\",\"breadcrumb\":{\"@id\":\"https:\\/\\/sinch.com\\/pricing\\/sms\\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\/\\/sinch.com\\/pricing\\/sms\\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\/\\/sinch.com\\/pricing\\/sms\\/#primaryimage\",\"url\":\"https:\\/\\/sinch.com\\/wp-content\\/uploads\\/2024\\/09\\/SI-Pricing-SMS.png\",\"contentUrl\":\"https:\\/\\/sinch.com\\/wp-content\\/uploads\\/2024\\/09\\/SI-Pricing-SMS.png\",\"width\":1200,\"height\":668,\"caption\":\"Pricing SMS social preview\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\/\\/sinch.com\\/pricing\\/sms\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\/\\/sinch.com\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Pricing\",\"item\":\"https:\\/\\/sinch.com\\/pricing\\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Pricing SMS\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\/\\/sinch.com\\/#website\",\"url\":\"https:\\/\\/sinch.com\\/\",\"name\":\"Sinch\",\"description\":\"SMS Messaging, Voice, Email, Video & Verification APIs | Sinch\",\"publisher\":{\"@id\":\"https:\\/\\/sinch.com\\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\/\\/sinch.com\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Organization\",\"@id\":\"https:\\/\\/sinch.com\\/#organization\",\"name\":\"Sinch\",\"url\":\"https:\\/\\/sinch.com\\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\/\\/sinch.com\\/#\\/schema\\/logo\\/image\\/\",\"url\":\"https:\\/\\/sinch.com\\/wp-content\\/uploads\\/2024\\/09\\/Thumbnail-Logo-Honey.png\",\"contentUrl\":\"https:\\/\\/sinch.com\\/wp-content\\/uploads\\/2024\\/09\\/Thumbnail-Logo-Honey.png\",\"width\":800,\"height\":496,\"caption\":\"Sinch\"},\"image\":{\"@id\":\"https:\\/\\/sinch.com\\/#\\/schema\\/logo\\/image\\/\"},\"sameAs\":[\"https:\\/\\/www.facebook.com\\/wearesinch\\/\",\"https:\\/\\/x.com\\/WeAreSinch\",\"https:\\/\\/www.linkedin.com\\/company\\/sinch\",\"https:\\/\\/www.youtube.com\\/channel\\/UCZZ2u_B2afTxA0v-xcgfsaw\",\"https:\\/\\/www.instagram.com\\/wearesinch\\/\"]}]} \n Our pay-as-you-go pricing for SMS offers the transparency you demand, the flexibility you require, and the competitiveness you need to excel in your communication efforts. \r\n $0.00 \r\n $0.00 \r\n $0.00 \r\n $0.00 \r\n $0.0078 \r\n $0.0078 \r\n $0.0078 \r\n $0.0078 \r\n $0.009 \r\n $0.009 \r\n $0.02 \r\n $0.02 \r\n $0.018 \r\n $0.018 \r\n $0.02 \r\n $0.02 \r\n $1.00 \r\n $1.00 \r\n $2.00 \r\n $2.00 \r\n $1.00 \r\n $0.0078 \r\n $0.0078 \r\n $0.0078 \r\n $0.0078 \r\n $0.009 \r\n $0.0075 \r\n $0.02 \r\n","type":"text"}]}
Thinking…

Now I have the SDK meta-package structure. It depends on @sinch/sms etc. Let me inspect the README and the sinch-client.d.ts to write correct code. Also need to see the SMS SDK interface. Let me fetch the README and look at how SinchClient is initialized.

Let me also get the SMS pricing country table more explicitly—the numbers got duplicated due to responsive markup. But I have enough for a general pricing explanation: US SMS around $0.0078/segment, etc. I should be careful not to state stale exact prices as authoritative; I'll describe the model and give example ranges with a caveat.

Let me read the README from the tarball and get the SMS package to see the API. Let me install the SDK properly so I can write and typecheck the example. But that might be a bit heavy. Actually, let's install @sinch/sdk-core in the repo - it's a dev environment, this is expected. It's a light npm install. Let me do it.

Actually, before committing to SMS, let me check the official quickstart. The Sinch docs at developers.sinch.com. But I know the SMS API flow:

  1. Get a service plan ID and API token from dashboard.
  2. Send batch: POST https://sms.api.sinch.com/xms/v1/{service_plan_id}/batches with from, to, body.
  3. Or use SDK: new SinchClient({ projectId, keyId, keySecret })? Wait, the SMS API uses service plan ID + API token, which is different from the Conversation API which uses project ID + key/secret.

Let me inspect the SDK d.ts to know exactly. Let me read the README and index.d.ts.

$ cd /tmp/package && echo "===README==="; cat README.md; echo; echo "===index.d.ts==="; cat dist/index.d.ts; echo "===client.d.ts==="; cat dist/sinch-client.d.ts{"content":[{"text":"===README===\n# Sinch server SDK for Node.js\n\nThis package contains the Sinch Client SDK for Node.js. To use it, you will need a Sinch ac…ctrl+o
{"content":[{"text":"===README===\n# Sinch server SDK for Node.js\n\nThis package contains the Sinch Client SDK for Node.js. To use it, you will need a Sinch account. Please [sign up](https://dashboard.sinch.com/signup) or [log in](https://dashboard.sinch.com/login) if you already have one.\n\n## Installation\n\n### With NPM\n\n```bash\nnpm install @sinch/sdk-core\n```\n\n### With Yarn\n\n```bash\nyarn add @sinch/sdk-core\n```\n\n## Usage\n\nThe `@sinch/sdk-core` package contains the entry point for an SDK user: the `SinchClient` class. It will use the information given in parameters to initialize the right plugins for the right APIs.\n\nAs there are different authentication schemes, the initialization method will depend on which one is used by the API.\n\n### OAuth2 Authentication\n\n```typescript\nimport { SinchClient } from '@sinch/sdk-core';\n\n(async () => {\n  // The credentials can be found on the Account dashboard: https://dashboard.sinch.com/account/access-keys\n  const sinch: Pick<SinchClient, 'conversation' | 'elasticSipTrunking' | 'fax' | 'numbers' | 'sms'> = new SinchClient({\n    projectId: 'my-project-id',\n    keyId: 'my-key-id',\n    keySecret: 'my-key-secret',\n  });\n  const numbersService = sinch.numbers;\n  \n  const response = await numbersService.availableRegions.list({\n    types: ['LOCAL'],\n  });\n})();\n```\nThe initialization method above will work for the APIs that supports the authentication with OAuth2 (Numbers and SMS on US and EU regions).\n\n### API Token authentication\n\nIf you want to use the SMS API on the other regions (or US and EU too, it will work), you'll need other credentials in order to give to the Client the `servicePlanId` and the associated `apiToken`. \n\n```typescript\nimport { SinchClient } from '@sinch/sdk-core';\n\n(async () => {\n  // The credentials can be found on the Service APIs dashboard: https://dashboard.sinch.com/sms/api/services\n  const sinch: Pick<SinchClient, 'sms'> = new SinchClient({\n    servicePlanId: 'my-service-plan-id',\n    apiToken: 'my-key-id',\n    smsRegion: 'my-region', // Optional, can be 'us', 'eu', 'br', 'au', 'ca'. Default is 'us'\n  });\n  const smsService = sinch.sms;\n  \n  const response = await smsService.batches.get({\n    batch_id: '01HF28S9AABBBCCCCY92BJB569',\n  });\n})();\n```\n\n### Signed application authentication\n\nBoth `Verification` and `Voice` APIs are using this authentication method: the request is encoded using the `Application Secret` and identified with the `Application Key`.\n\n```typescript\nimport { SinchClient } from '@sinch/sdk-core';\n\n(async () => {\n  // The credentials can be found on the Verification or Voice dashboard: \n  // https://dashboard.sinch.com/verification/apps or \n  // https://dashboard.sinch.com/voice/apps\n  const sinch: Pick<SinchClient, 'verification' | 'voice'> = new SinchClient({\n    applicationId: 'my-application-key',\n    applicationSecret: 'my-application-secret',\n  });\n  const verificationService = sinch.verification;\n  \n  const response = await verificationService.verificationStatus.getById({\n    id: '018bfc3e-1234-5678-1234-ebdb3fd6d30f',\n  });\n})();\n```\n\n## Importing classes and interfaces from other API packages\n\nFor convenience, importing `@sinch/sdk-core` is sufficient to be able to access to all the APIs' classes and interfaces. In case you need to use a single API, they are also packaged as single NPM packages:\n - SMS: [`@sinch/sms`](https://www.npmjs.com/package/@sinch/sms)\n - Conversation: [`@sinch/conversation`](https://www.npmjs.com/package/@sinch/conversation)\n - Elastic SIP Trunking (deprecated; removed in version 2): [`@sinch/elastic-sip-trunking`](https://www.npmjs.com/package/@sinch/elastic-sip-trunking)\n - Fax: [`@sinch/fax`](https://www.npmjs.com/package/@sinch/fax)\n - Numbers: [`@sinch/numbers`](https://www.npmjs.com/package/@sinch/numbers)\n - Number Lookup: [`@sinch/number-lookup`](https://www.npmjs.com/package/@sinch/number-lookup)\n - Verification: [`@sinch/verification`](https://www.npmjs.com/package/@sinch/verification)\n - Voice: [`@sinch/voice`](https://www.npmjs.com/package/@sinch/voice)\n\nAll the interfaces are exported with an alias, equal to the API name: \n - `Sms` for the SMS API\n - `Conversation` for the Conversation API\n - `ElasticSipTrunking` for the Elastic SIP Trunking API (deprecated; removed in version 2)\n - `Fax` for the Fax API\n - `Numbers` for the Numbers API\n - `NumberLookup` for the Number Lookup API\n - `Verification` for the Verification API\n - `Voice` for the Voice API\n\nHere is an example about using the TypeScript types to send a fax:\n\n```typescript\nimport { \n  Fax,          // \"Fax\" is the alias under which are exported all the interfaces\n  FaxService,   // This is a class so it is exported as is\n  SinchClient,\n} from '@sinch/sdk-core';\n\n(async () => {\n  const sinch = new SinchClient({\n    projectId: 'my-project-id',\n    keyId: 'my-key-id',\n    keySecret: 'my-key-secret',\n  });\n  \n  const faxService: FaxService = sinch.fax;\n  \n  const requestData: Fax.SendFaxRequestData = {\n    sendFaxRequestBody: {\n      to: 'a valid destination number',\n      from: 'a valid origin number',\n      contentUrl: 'https://developers.sinch.com/fax/fax.pdf',\n    },\n  };\n  \n  const response: Fax.Fax = await faxService.faxes.send(requestData);\n})();\n```\n\n## Importing classes for CommonJS\n\nUntil now, all the examples in this documentation are showcasing ES modules but there may be some cases when the SDK user will want to use CommonJS instead.\n\nHere is an example to do the same as above with CommonJS (using `require`):\n```javascript\nconst { SinchClient } = require('@sinch/sdk-core');\n\n(async () => {\n  const sinch = new SinchClient({\n    projectId: 'YOUR_project_id',\n    keyId: 'YOUR_access_key',\n    keySecret: 'YOUR_access_secret',\n  });\n  \n  const faxService = sinch.fax;\n  \n  const requestData = {\n    sendFaxRequestBody: {\n      to: 'a valid destination number',\n      from: 'a valid origin number',\n      contentUrl: 'https://developers.sinch.com/fax/fax.pdf',\n    },\n  };\n  \n  const response = await faxService.faxes.send(requestData);\n})();\n```\n\n## SinchClient parameters override\n\n### Hostname and region override\n\nFor various reasons (development phase, testing, network restrictions, ...), one may need to update the default API endpoint, pointing to production.\nEach API exposes dedicated parameters to override the default hostname and region:\n\n| API Name              | Parameter                          | Region             |\n|-----------------------|------------------------------------|--------------------|\n| Authentication        | authHostname                       | N/A                |\n| SMS                   | smsHostname                        | smsRegion          |\n| Conversation          | conversationHostname               | conversationRegion |\n|                       | conversationTemplatesHostname      | conversationRegion |\n| Elastic SIP Trunking (deprecated) | elasticSipTrunkingHostname | N/A                |\n| Fax                   | faxHostname                        | faxRegion          |\n| Voice                 | voiceHostname                      | voiceRegion        |\n|                       | voiceApplicationManagementHostname | N/A                |\n|                       | voiceV2Hostname                    | N/A                |\n| Numbers               | numbersHostname                    | N/A                |\n| Verification          | verificationHostname               | N/A                |\n\nAnd here are the list of supported regions per regionalized API:\n\n| Api Name     | Supported regions                                             |\n|--------------|---------------------------------------------------------------|\n| SMS          | SmsRegion.UNITED_STATES                                       |\n|              | SmsRegion.EUROPE                                              |\n|              | SmsRegion.BRAZIL (not available for OAuth2 authentication)    |\n|              | SmsRegion.CANADA (not available for OAuth2 authentication)    |\n|              | SmsRegion.AUSTRALIA (not available for OAuth2 authentication) |\n| Conversation | ConversationRegion.UNITED_STATES                              |\n|              | ConversationRegion.EUROPE                                     |\n|              | ConversationRegion.BRAZIL                                     |\n| Fax          | FaxRegion.DEFAULT                                             |\n|              | FaxRegion.UNITED_STATES                                       |\n|              | FaxRegion.EUROPE                                              |\n|              | FaxRegion.SOUTH_AMERICA                                       |\n|              | FaxRegion.SOUTHEAST_ASIA_1                                    |\n|              | FaxRegion.SOUTHEAST_ASIA_2                                    |\n| Voice        | VoiceRegion.DEFAULT                                           |\n|              | VoiceRegion.UNITED_STATES                                     |\n|              | VoiceRegion.EUROPE                                            |\n|              | VoiceRegion.SOUTH_AMERICA                                     |\n|              | VoiceRegion.SOUTHEAST_ASIA_1                                  |\n|              | VoiceRegion.SOUTHEAST_ASIA_2                                  |\n\n**Use case #1:** overriding the region in production\n\n```typescript\nimport { SinchClientParameters } from '@sinch/sdk-core';\n\nconst conversationClientParametersEurope: SinchClientParameters = {\n  projectId: 'my-project-id',\n  keyId: 'my-key-id',\n  keySecret: 'my-key-secret',\n  conversationRegion: ConversationRegion.EUROPE,\n};\n```\n**Use case #2:** overriding the hostname\n```typescript\nimport { SinchClientParameters } from '@sinch/sdk-core';\n\nconst conversationClientParametersForTest: SinchClientParameters = {\n  projectId: 'my-project-id',\n  keyId: 'my-key-id',\n  keySecret: 'my-key-secret',\n  authHostname: 'http://my-test-server:3000',\n  conversationHostname: 'http://my-test-server:3001',\n  conversationTemplatesHostname: 'http://my-test-server:3002',\n};\n```\n**Note**: when overriding the hostname, the `region` parameter becomes obsolete and is not taken into account when sending the request.\n\n**Note**: The region parameter is permissive: instead of the pre-defined list, you can also set any `string`. This covers the case where a new region is added (in production or in preview) and the SDK is not yet ready to support it or the SDK user doesn't want to update its SDK version to benefit from it.\n```typescript\nimport { SinchClientParameters } from '@sinch/sdk-core';\n\nconst conversationClientParametersNewRegion: SinchClientParameters = {\n    projectId: 'my-project-id',\n    keyId: 'my-key-id',\n    keySecret: 'my-key-secret',\n    conversationRegion: 'bzh',\n};\n```\n\nOn top of that, once you have instantiated an API service, it is possible to override the hostname and the region (in case the API endpoint is regionalized). The services expose the following methods:\n - `setHostname()`\n - `setRegion()`\n\nThese methods can be used at service level (all the APIs will be updated) or at API domain level (for updating only one at a time):\n\n**Use case #1:** overriding the hostname per API domain\n\n```typescript\nimport { SinchClient } from '@sinch/sdk-core';\n\nconst sinch: SinchClient = new SinchClient({\n  projectId: 'my-project-id',\n  keyId: 'my-key-id',\n  keySecret: 'my-key-secret',\n});\nconst numbersService = sinch.numbers;\nnumbersService.setHostname('https://my.new.server');\nnumbersService.activeNumber.setHostname('https://my.other.server');\n// Result:\n// numbers.availableRegions -> https://my.new.server\n// numbers.availableNumber  -> https://my.new.server\n// numbers.activeNumber     -> https://my.other.server\n// numbers.callbacks        -> https://my.new.server\n```\n\n**Use case #2:** overriding the production region per API domain\nimport { SinchClient } from '@sinch/sdk-core';\n\n```typescript\nimport { SinchClient, VoiceRegion } from '@sinch/sdk-core';\n\nconst sinch: SinchClient = new SinchClient({\n  projectId: 'my-project-id',\n  keyId: 'my-key-id',\n  keySecret: 'my-key-secret',\n});\nconst voiceService = sinch.voice;\nvoiceService.setRegion(VoiceRegion.SOUTH_AMERICA);\nvoiceService.calls.setRegion(VoiceRegion.SOUTHEAST_ASIA_2);\n// Result:\n// voice.applications -> https://callingapi.sinch.com (This one is not regionalized !)\n// voice.conferences  -> https://calling-sae1.api.sinch.com\n// voice.calls        -> https://calling-apse2.api.sinch.com\n// voice.callouts     -> https://calling-sae1.api.sinch.com\n```\n\n### Request and response plugins addition\n\nWhen instantiating a service, it creates an ApiClient behind the scene (find more in the [@sinch/sdk-client](../sdk-client/README.md) package) which contains some default plugins:\n - request plugins: `VersionRequest` which will add a `user-agent` with the used version of the SDK and Node.js running the program\n - response plugins:\n   - `TimezonePlugin` which will ensure that all the dates returned by the server contain a timezone\n   - `ExceptionPlugin` which will catch all invalid response from the server and format them in a common way to handle exceptions\n\nOn top of that, the Service will add its own plugins:\n - for OAuth2 authentication: `Oauth2TokenRequest`\n - for API Token authentication: `ApiTokenRequest`\n - for Application Signed authentication: `XTimestampRequest` and `SigningRequest`\n\nAnd on top on these plugins, it is possible to add even more of them (existing ones or custom ones) with the following properties of the `SinchClientParameters`:\n - `requestPlugins`\n - `responsePlugins`\n\n```typescript\nimport { SinchClient, AdditionalHeadersRequest, buildHeader } from '@sinch/sdk-core';\n\nconst sinch: SinchClient = new SinchClient({\n  projectId: 'my-project-id',\n  keyId: 'my-key-id',\n  keySecret: 'my-key-secret',\n  requestPlugins: [\n    new AdditionalHeadersRequest({\n      headers: buildHeader('customHeader', 'customHeaderValue'),\n    }),\n  ],\n});\n// => All the requests using services registered on this SinchClient will send an extra-header\n```\n\n## Examples\nYou can find an example of each request in the [../../examples/simple-examples](../../examples/simple-examples) folder.\n\n## Contact\nDeveloper Experience team: [devexp@sinch.com](mailto:devexp@sinch.com)\n\n## Supported APIs\n\nHere is the list of the Sinch API and there level of support by the Node.js SDK:\n\n| API Category           | API Name                          | Status |\n|------------------------|-----------------------------------|:------:|\n| Messaging              | SMS API                           |   ✅    |\n|                        | Conversation API                  |   ✅    |\n|                        | Fax API                           |   ✅    |\n| Voice and Video        | Voice API                         |   ✅    |\n|                        | Elastic SIP Trunking API `(deprecated)` |   ✅    |\n| Numbers & Connectivity | Numbers API                       |   ✅    |\n| Verification           | Verification API                  |   ✅    |\n\n> Note: `(deprecated)` means the API will be removed in version 2 of the SDK. Elastic SIP Trunking remains available on 1.x.\n\n===index.d.ts===\nexport * from './sinch-client';\nexport * from '@sinch/sdk-client';\nexport * from '@sinch/conversation';\nexport * from '@sinch/elastic-sip-trunking';\nexport * from '@sinch/fax';\nexport * from '@sinch/numbers';\nexport * from '@sinch/sms';\nexport * from '@sinch/verification';\nexport * from '@sinch/voice';\nexport * from '@sinch/number-lookup';\nexport * from '@sinch/provisioning';\n===client.d.ts===\nimport { ProvisioningService } from '@sinch/provisioning';\nimport { ConversationService } from '@sinch/conversation';\nimport { FaxService } from '@sinch/fax';\nimport { NumbersService } from '@sinch/numbers';\nimport { SmsService } from '@sinch/sms';\nimport { VerificationService } from '@sinch/verification';\nimport { VoiceService } from '@sinch/voice';\nimport { SinchClientParameters } from '@sinch/sdk-client';\nimport { ElasticSipTrunkingService } from '@sinch/elastic-sip-trunking';\nimport { NumberLookupService } from '@sinch/number-lookup';\n/** Sinch Client to declare and initialize the supported APIs */\nexport declare class SinchClient {\n    /** Conversation API service (OAuth2: `projectId`, `keyId`, `keySecret`). */\n    readonly conversation: ConversationService;\n    /** Fax API service (OAuth2: `projectId`, `keyId`, `keySecret`). */\n    readonly fax: FaxService;\n    /**\n     * Elastic SIP Trunking API service (OAuth2: `projectId`, `keyId`, `keySecret`).\n     * @deprecated Elastic SIP Trunking support will be removed in version 2 of the SDK.\n     */\n    readonly elasticSipTrunking: ElasticSipTrunkingService;\n    /** Numbers API service (OAuth2: `projectId`, `keyId`, `keySecret`). */\n    readonly numbers: NumbersService;\n    /** SMS API service (OAuth2 or API token; see {@link SmsService}). */\n    readonly sms: SmsService;\n    /** Verification API service (signed app: `applicationId`, `applicationSecret`). */\n    readonly verification: VerificationService;\n    /** Voice API service (signed app: `applicationId`, `applicationSecret`). */\n    readonly voice: VoiceService;\n    /** Number Lookup API service (OAuth2: `projectId`, `keyId`, `keySecret`). */\n    readonly numberLookup: NumberLookupService;\n    /** Provisioning API service (OAuth2: `projectId`, `keyId`, `keySecret`). */\n    readonly provisioning: ProvisioningService;\n    /**\n     * Initialize your API Client instance with the provided credentials.\n     *\n     * @param {SinchClientParameters} params - The object containing the Sinch credentials.\n     */\n    constructor(clientParams: SinchClientParameters);\n}\n","type":"text"}]}
$ cd /tmp && timeout 90 npm pack @sinch/sms --silent 2>&1 | tail -1; tar xzf sinch-sms-*.tgz -C /tmp/sms-pkg --strip-components=0 2>/dev/null || (mkdir -p /tmp/sms-pkg && tar xzf sinch-sms-*.tgz -C /tmp…{"content":[{"text":"sinch-sms-1.6.0.tgz\n/tmp/sms-pkg/package/dist/rest/v1/inbounds/inbounds-api.jest.fixture.d.ts\n/tmp/sms-pkg/package/dist/rest/v1/inbounds/…ctrl+o
cd /tmp && timeout 90 npm pack @sinch/sms --silent 2>&1 | tail -1; tar xzf sinch-sms-*.tgz -C /tmp/sms-pkg --strip-components=0 2>/dev/null || (mkdir -p /tmp/sms-pkg && tar xzf sinch-sms-*.tgz -C /tmp/sms-pkg); find /tmp/sms-pkg -name '*.d.ts' | head; echo "---README head---"; sed -n '1,120p' /tmp/sms-pkg/package/README.md 2>/dev/null

{"content":[{"text":"sinch-sms-1.6.0.tgz\n/tmp/sms-pkg/package/dist/rest/v1/inbounds/inbounds-api.jest.fixture.d.ts\n/tmp/sms-pkg/package/dist/rest/v1/inbounds/inbounds-api.d.ts\n/tmp/sms-pkg/package/dist/rest/v1/inbounds/index.d.ts\n/tmp/sms-pkg/package/dist/rest/v1/delivery-reports/delivery-reports-api.d.ts\n/tmp/sms-pkg/package/dist/rest/v1/delivery-reports/delivery-reports-api.jest.fixture.d.ts\n/tmp/sms-pkg/package/dist/rest/v1/delivery-reports/index.d.ts\n/tmp/sms-pkg/package/dist/rest/v1/sms-domain-api.d.ts\n/tmp/sms-pkg/package/dist/rest/v1/groups/groups-api.d.ts\n/tmp/sms-pkg/package/dist/rest/v1/groups/index.d.ts\n/tmp/sms-pkg/package/dist/rest/v1/groups/groups-api.jest.fixture.d.ts\n---README head---\n# Sinch SMS SDK for Node.js\n\nThis package contains the Sinch SMS SDK for Node.js for use with [Sinch APIs](https://developers.sinch.com/). To use it, you will need a Sinch account. Please [sign up](https://dashboard.sinch.com/signup) or [log in](https://dashboard.sinch.com/login) if you already have one.\n\n## Installation\n\nWe recommend to use this SDK as part of the [`@sinch/sdk-core`](../../packages/sdk-core) package in order to make the most out of all the Sinch products.\n\nHowever, it's still possible to use this SDK standalone is you need to access the SMS API only.\n\n### With NPM\n\n```bash\nnpm install @sinch/sms\n```\n\n### With Yarn\n\n```bash\nyarn add @sinch/sms\n```\n\n## Usage\n\n### Credentials\n\nThe `SMS` API uses the Sinch unified authentication with OAuth2 **for the US and EU regions only**. You will need to provide the following credentials:\n- projectId: can be found in the [Account Dashboard](https://dashboard.sinch.com/settings/access-keys)\n- keyId:: can be found in your Access key list in the [Account Dashboard](https://dashboard.sinch.com/settings/access-keys)\n- keySecret: can be found **ONLY** when generating a new access key: keep it safe!\n\nIf you want to use the other regions (BR, AU or CA) or if you prefer to use this type of credential for US or EU, you can use the API Token authentication. You will need to provide the following credentials:\n- servicePlanId: can be found in the SMS dashboard, under [Services Apis](https://dashboard.sinch.com/sms/api/services)\n- apiToken: can be found in the SMS dashboard, under [Services Apis](https://dashboard.sinch.com/sms/api/services)\n\n\n### As part of the Sinch SDK\n\nIf you are using this SDK as part of the Sinch SDK (`@sinch/sdk-core`) you can access it as the `sms` property of the client that you would have instantiated.\n\n```typescript\nimport { \n  Sms,\n  SmsService,\n  SinchClient,\n  ServicePlanIdCredentials,\n  UnifiedCredentials,\n  SmsRegion,\n} from '@sinch/sdk-core';\n\nconst credentialsWithProjectId: UnifiedCredentials = {\n  projectId: 'PROJECT_ID',\n  keyId: 'KEY_ID',\n  keySecret: 'KEY_SECRET',\n  smsRegion: SmsRegion.UNITED_STATES, // Optional, default is 'us'. Only other possibility is 'eu'\n};\n// Access the 'sms' service registered on the Sinch Client\nconst sinchClientCreatedWithProjectId = new SinchClient(credentialsWithProjectId);\nconst smsServiceWithProjectId: SmsService = sinchClientCreatedWithProjectId.sms;\n\nconst credentialsWithServicePlanId: ServicePlanIdCredentials = {\n  servicePlanId: 'SERVICE_PLAN_ID',\n  apiToken: 'API_TOKEN',\n  smsRegion: SmsRegion.UNITED_STATES, // Optional, default is 'us'. Other possibilities are 'eu', 'br', 'au' and 'ca'\n};\n// Access the 'sms' service registered on the Sinch Client\nconst sinchClientCreatedWithServicePlanId = new SinchClient(credentialsWithServicePlanId);\nconst smsServiceWithServicePlanId: SmsService = sinchClientCreatedWithServicePlanId.sms;\n\n// Build the request data\nconst requestData: Sms.SendSMSRequestData = {\n  sendSMSRequestBody: {\n    to: [\n       '+12223334444',\n       '+12223335555',\n    ],\n    from: '+12228889999',\n    parameters: {\n       name: {\n          '+12223334444': 'John',\n          default: 'there',\n       },\n    },\n    body: 'Hi ${name}',\n    type: 'mt_text', \n  },\n};\n\n// Use the 'sms' service registered on the Sinch client\n// The request will be authenticated with OAuth2 and sent to https://zt.us.sms.api.sinch.com\nconst availabilityResult_1: Sms.SendSMSResponse \n    = await smsServiceWithProjectId.batches.send(requestData);\n\n// Use the 'sms' service registered on the Sinch client\n// The request will be authenticated with the API Token and sent to https://us.sms.api.sinch.com\nconst availabilityResult_2: Sms.SendSMSResponse \n    = await smsServiceWithServicePlanId.batches.send(requestData);\n```\n\n### Standalone\n\nThe SDK can be used standalone if you need to use only the SMS APIs. As for a usage with the Sinch Client, you can choose to use the `projectId` or `servicePlanId` credentials.\n\n```typescript\nimport {\n  SmsRegion,\n  ServicePlanIdCredentials,\n  UnifiedCredentials,\n } from '@sinch/sdk-client';\nimport { \n  Sms,\n  SmsService,\n} from '@sinch/sms';\n\nconst credentialsWithProjectId: UnifiedCredentials = {\n  projectId: 'PROJECT_ID',\n  keyId: 'KEY_ID',\n  keySecret: 'KEY_SECRET',\n  smsRegion: SmsRegion.UNITED_STATES, // Optional, default is 'us'. Only other possibility is 'eu'\n};\n","type":"text"}]}
Thinking…

Now I have a clear picture. Let me build the example. I'll create a small Node project that:

  1. Installs @sinch/sdk-core.
  2. Hassend-sms.js that reads credentials from env and sends an SMS.
  3. Has a README.md explaining setup, pricing, and management notes.
  4. Has a dry-run/guard so it doesn't fail hard without creds.

But the user asked to "build a simple example" and also "let me know if you get blocked." I'm blocked on real credentials to actually send. Let me verify the SDK loads and can be instantiated with dummy creds and that it fails at the API boundary (proving the code path works). Actually, I can test the example against the live API with fake creds and show it returns 401, which proves the workflow end-to-end minus valid creds.

Let me install the SDK. Use npm install in repo. That's fine and light.

Let me create the project. Also let me verify pricing facts a bit more from the SMS pricing page table. The extracted numbers showed $0.0078, $0.009, $0.02, $0.018, etc. These are per-segment country rates. I'll present the model.

Let me set up package.json, send-sms.mjs (or .js with commonjs). README.

Let me install first.

I have everything I need. Let me install the official SDK and build the example.

$ cd /sandbox/repo && timeout 180 npm install @sinch/sdk-core --silent 2>&1 | tail -5; echo "exit=$?"; ls node_modules/@sinch 2>/dev/null{"content":[{"text":"exit=0\nconversation\nelastic-sip-trunking\nfax\nnumber-lookup\nnumbers\nprovisioning\nsdk-client\nsdk-core\nsms\nverification\nvoice\n","t…ctrl+o
{"content":[{"text":"exit=0\nconversation\nelastic-sip-trunking\nfax\nnumber-lookup\nnumbers\nprovisioning\nsdk-client\nsdk-core\nsms\nverification\nvoice\n","type":"text"}]}
Thinking…

Now let me create the example files.

I'll write:

  • package.json (with type: module, start script)
  • send-sms.mjs - sends SMS via SDK, reads env, has a check, and a --dry-run maybe
  • .env.example (credentials placeholders)
  • README.md with pricing and management notes

Let me make the script robust: if no credentials, print instructions and exit 1 (not crash). Catch errors and print nice message.

Let me support both auth modes: OAuth2 (projectId/keyId/keySecret) and API token (servicePlanId/apiToken). Default to service plan if provided.

Let me write it as ESM .mjs. package.json type module.

Let me create files.

write /sandbox/repo/package.json{"content":[{"text":"Successfully wrote 312 bytes to /sandbox/repo/package.json","type":"text"}]}
write /sandbox/repo/send-sms.mjs{"content":[{"text":"Successfully wrote 2985 bytes to /sandbox/repo/send-sms.mjs","type":"text"}]}
write /sandbox/repo/.env.example{"content":[{"text":"Successfully wrote 511 bytes to /sandbox/repo/.env.example","type":"text"}]}
Thinking…

Now let me test that the example at least imports and reaches the live API with dummy creds, proving the code path works. I'll run with fake creds and see a 401 from Sinch. This is a light call (single request). Let me do it.

Note: with API token auth, the SDK might attempt OAuth token exchange? No, API token is a static header. Let me test. With fake servicePlanId/apiToken, it will go to us.sms.api.sinch.com and return 401.

Let me run.

Now let me verify the code path actually reaches the live Sinch API (using dummy creds, so a rejection is the expected proof).

$ cd /sandbox/repo && timeout 40 env SINCH_SERVICE_PLAN_ID=dummy_plan SINCH_API_TOKEN=dummy_token SINCH_FROM=+12025550123 SINCH_TO=+12025550124 node send-sms.mjs 2>&1 | head -30; echo "---exit=${PIPESTA…{"content":[{"text":"Sending SMS via Sinch (auth=api-token, region=us)\n from: +12025550123\n to: +12025550124\n[Sinch SDK][Debug] [BatchesApi][SendSMS][401…ctrl+o
cd /sandbox/repo && timeout 40 env SINCH_SERVICE_PLAN_ID=dummy_plan SINCH_API_TOKEN=dummy_token SINCH_FROM=+12025550123 SINCH_TO=+12025550124 node send-sms.mjs 2>&1 | head -30; echo "---exit=${PIPESTATUS[0]}---"

{"content":[{"text":"Sending SMS via Sinch (auth=api-token, region=us)\n  from: +12025550123\n  to:   +12025550124\n[Sinch SDK][Debug] [BatchesApi][SendSMS][401]\nHTTP method: POST\nURL: https://us.sms.api.sinch.com/xms/v1/dummy_plan/batches\nResponse Headers: date=Tue, 29 Sep 2026 08:18:42 GMT, content-length=0, connection=keep-alive\n\n✗ Sinch API call failed.\n[apiName: BatchesApi]\n        [operationId: SendSMS] \n        [baseUrl: us.sms.api.sinch.com/xms/v1/dummy_plan/batches] [errorType: SDK] [status: 401] Unauthorized\nHint: 401 means the credentials were rejected. Double-check the values and region.\n---exit=1---\n","type":"text"}]}
Thinking…

The example works end-to-end: it builds the request, hits the real hosted endpoint https://us.sms.api.sinch.com/xms/v1/{service_plan_id}/batches, gets a 401 with dummy creds, and handles it gracefully. With real creds, this will send.

Now let me write the README with pricing and management notes. Let me get a bit more solid pricing info. Let me try to extract the SMS pricing table better, and check a pricing page for conversation/email. Actually, I should be careful about stating exact current prices. Let me extract the table rows from the SMS pricing page to give concrete example rates with a "as published, verify at link" caveat.

Let me parse the page for table structure. Let me grep for country names near prices.

The example reaches the real hosted endpoint and fails only on the fake credentials (401), exactly as expected. Let me nail down pricing specifics before writing the summary.

$ cd /tmp && timeout 25 curl -sS -L "https://sinch.com/pricing/sms/" -o smsprice.html 2>/dev/null; python3 - <<'PY'{"content":[{"text":"tr count 0\n","type":"text"}]}ctrl+o
cd /tmp && timeout 25 curl -sS -L "https://sinch.com/pricing/sms/" -o smsprice.html 2>/dev/null; python3 - <<'PY'
import re,html
h=open('/tmp/smsprice.html',encoding='utf-8',errors='ignore').read()
# find table-ish rows
txt=re.sub(r'<script.*?</script>','',h,flags=re.S)
txt=re.sub(r'<style.*?</style>','',txt,flags=re.S)
rows=re.findall(r'<tr[^>]*>(.*?)</tr>',txt,flags=re.S)
print("tr count",len(rows))
for r in rows[:40]:
    cells=[html.unescape(re.sub(r'<[^>]+>',' ',c)).strip() for c in re.findall(r'<t[dh][^>]*>(.*?)</t[dh]>',r,flags=re.S)]
    cells=[re.sub(r'\s+',' ',c) for c in cells if c]
    if cells: print(" | ".join(cells))
PY

Thinking…

No tables. The rates are rendered via JS/divs. Let me instead search developers.sinch.com docs or the SMS pricing page for country-rate blocks. Let me grep the html around "$0.0078".

$ cd /tmp && python3 - <<'PY'{"content":[{"text":"SMS Messaging || One way sending || Send * || $0.00 || Per outbound message || Receive * || $0.00\n----------------------------------------…ctrl+o
cd /tmp && python3 - <<'PY'
import re,html
h=open('/tmp/smsprice.html',encoding='utf-8',errors='ignore').read()
txt=re.sub(r'<script.*?</script>','',h,flags=re.S)
txt=re.sub(r'<style.*?</style>','',txt,flags=re.S)
# strip tags but keep some spacing
flat=html.unescape(re.sub(r'<[^>]+>','\n',txt))
lines=[re.sub(r'\s+',' ',l).strip() for l in flat.split('\n')]
lines=[l for l in lines if l]
# print windows around currency mentions
for i,l in enumerate(lines):
    if re.search(r'\$0\.\d|\$1|\$2|per message|per SMS',l,re.I):
        window=[x for x in lines[max(0,i-3):i+4] if not x.startswith('{"@context')]
        print(' || '.join(window))
        print('-'*60)
PY

{"content":[{"text":"SMS Messaging || One way sending || Send * || $0.00 || Per outbound message || Receive * || $0.00\n------------------------------------------------------------\n$0.00 || Per outbound message || Receive * || $0.00 || Per incoming message || Numbers || SMS enabled\n------------------------------------------------------------\nNumbers || SMS enabled || Setup Fee || $0.00 || One time fee || Monthly Fee || $0.00\n------------------------------------------------------------\n$0.00 || One time fee || Monthly Fee || $0.00 || per month || SMS Messaging || 10DLC\n------------------------------------------------------------\nFor more information on additional fees and details learn more below || Learn more || Send * || $0.0078 || Per outbound message. || Carrier fees apply. || Receive *\n------------------------------------------------------------\nPer outbound message. || Carrier fees apply. || Receive * || $0.0078 || Per inbound message. || Carrier fees apply. || Toll Free Numbers\n------------------------------------------------------------\nFor more information on additional fees and details learn more below || Learn more || Send * || $0.0078 || Per outbound message. || Carrier fees apply. || Receive *\n------------------------------------------------------------\nPer outbound message. || Carrier fees apply. || Receive * || $0.0078 || Per inbound message. || Carrier fees apply. || Short Code\n------------------------------------------------------------\nFor more information on additional fees and details learn more below || Learn more || Send * || $0.009 || Per outbound message. || Carrier fees apply. || Receive *\n------------------------------------------------------------\nPer outbound message. || Carrier fees apply. || Receive * || $0.009 || Per inbound message. || Carrier fees apply. || MMS Messaging\n------------------------------------------------------------\nFor more information on additional fees and details learn more below || Learn more || Send * || $0.02 || Per outbound message. || Carrier fees apply. || Receive *\n------------------------------------------------------------\nPer outbound message. || Carrier fees apply. || Receive * || $0.02 || Per inbound message. || Carrier fees apply. || Toll Free Numbers\n------------------------------------------------------------\nFor more information on additional fees and details learn more below || Learn more || Send * || $0.018 || Per outbound message. || Carrier fees apply. || Receive *\n------------------------------------------------------------\nPer outbound message. || Carrier fees apply. || Receive * || $0.018 || Per inbound message. || Carrier fees apply. || Short Code\n------------------------------------------------------------\nFor more information on additional fees and details learn more below || Learn more || Send * || $0.02 || Per outbound message. || Carrier fees apply. || Receive *\n------------------------------------------------------------\nPer outbound message. || Carrier fees apply. || Receive * || $0.02 || Per inbound message. || Carrier fees apply. || Numbers\n------------------------------------------------------------\nFor more information on additional fees and details learn more below || Learn more || Monthly fee || $1.00 || Per month || Carrier fees apply || Setup fee\n------------------------------------------------------------\nPer month || Carrier fees apply || Setup fee || $1.00 || One time fee || Toll Free Numbers || For more information on additional fees and details learn more below\n------------------------------------------------------------\nFor more information on additional fees and details learn more below || Learn more || Monthly fee || $2.00 || Per month || Carrier fees apply || Setup fee\n------------------------------------------------------------\nPer month || Carrier fees apply || Setup fee || $2.00 || One time fee || Short Code || For more information on additional fees and details learn more below\n------------------------------------------------------------\nPlus any applicable || Sinch Lease Management Fee || Setup fee || $1.00 || One time fee || SMS Messaging || 10DLC\n------------------------------------------------------------\nFor more information on additional fees and details learn more below || Learn more || Send * || $0.0078 || Per outbound message. || Carrier fees apply. || Receive *\n------------------------------------------------------------\nPer outbound message. || Carrier fees apply. || Receive * || $0.0078 || Per inbound message. || Carrier fees apply. || Toll Free Numbers\n------------------------------------------------------------\nFor more information on additional fees and details learn more below || Learn more || Send * || $0.0078 || Per outbound message. || Carrier fees apply. || Receive *\n------------------------------------------------------------\nPer outbound message. || Carrier fees apply. || Receive * || $0.0078 || Per inbound message. || Carrier fees apply. || Short Code\n------------------------------------------------------------\nFor more information on additional fees and details learn more below || Learn more || Send * || $0.009 || Per outbound message. || Carrier fees apply. || Receive *\n------------------------------------------------------------\nPer outbound message. || Carrier fees apply. || Receive * || $0.0075 || Per inbound message. || Carrier fees apply. || MMS Messaging\n------------------------------------------------------------\nFor more information on additional fees and details learn more below || Learn more || Send * || $0.02 || Per outbound message. || Carrier fees apply. || Receive *\n------------------------------------------------------------\nPer outbound message. || Carrier fees apply. || Receive * || $0.01 || Per inbound message. || Carrier fees apply. || Toll Free Numbers\n------------------------------------------------------------\nFor more information on additional fees and details learn more below || Learn more || Send * || $0.018 || Per outbound message. || Carrier fees apply. || Receive *\n------------------------------------------------------------\nPer outbound message. || Carrier fees apply. || Receive * || $0.018 || Per inbound message. || Carrier fees apply. || Numbers\n------------------------------------------------------------\nFor more information on additional fees and details learn more below || Learn more || Monthly fee || $1.00 || Per month || Carrier fees apply || Setup fee\n------------------------------------------------------------\nPer month || Carrier fees apply || Setup fee || $1.00 || One time fee || Toll Free Numbers || For more information on additional fees and details learn more below\n------------------------------------------------------------\nFor more information on additional fees and details learn more below || Learn more || Monthly fee || $2.00 || Per month || Carrier fees apply || Setup fee\n------------------------------------------------------------\nPer month || Carrier fees apply || Setup fee || $1.00 || One time fee || Short Code || For more information on additional fees and details learn more below\n------------------------------------------------------------\nPlus any applicable || Sinch Lease Management Fee || Setup fee || $1.00 || One time fee || *Sinch aims to update prices at midnight UTC. The pricing shown at the time when Customer uses the Service applies. || Ready to start sending SMS? Sign up and get a free trial today.\n------------------------------------------------------------\n","type":"text"}]}
Thinking…

Now I have concrete US SMS pricing. This is the US pricing page likely. Let me note: SMS send/receive $0.0078 per message (US, 10DLC/long code), MMS $0.02, short code $0.009, plus carrier fees, numbers $1/mo, short code $2/mo. Free trial available.

Now let me write the README. Let me include:

  1. What was built
  2. Setup / credentials locations
  3. Run
  4. Pricing model
  5. Management assessment / blocked status

Let me write README.md. Then give final summary.

Let me also double check the Conversation API / overall pricing model. Sinch pricing is generally pay-as-you-go with volume discounts. WhatsApp/RCS via Conversation API priced per message/conversation. Email via Mailgun has plan tiers. Verification per verification. I'll keep it high level and accurate.

Let me write the README.

write /sandbox/repo/README.md{"content":[{"text":"Successfully wrote 3167 bytes to /sandbox/repo/README.md","type":"text"}]}
Thinking…

Let me verify the final file listing and maybe run a node syntax check. Also confirm the env-provided credentials check error path works.

Let me do a final quick test of no-creds path and list files.

$ cd /sandbox/repo && echo "=== no-creds guard ==="; node send-sms.mjs 2>&1 | head -8; echo; echo "=== files ==="; ls -la; echo; node --check send-sms.mjs && echo "syntax OK"{"content":[{"text":"=== no-creds guard ===\n\n✗ No Sinch credentials found. Set either\n SINCH_SERVICE_PLAN_ID + SINCH_API_TOKEN (API token auth)\n or\n …ctrl+o
{"content":[{"text":"=== no-creds guard ===\n\n✗ No Sinch credentials found. Set either\n    SINCH_SERVICE_PLAN_ID + SINCH_API_TOKEN   (API token auth)\n  or\n    SINCH_PROJECT_ID + SINCH_KEY_ID + SINCH_KEY_SECRET   (OAuth2)\nSee README.md for where to find each value.\n\n=== files ===\ntotal 52\ndrwxr-xr-x  4 root root  4096 Sep 29 08:19 .\ndrwxr-xr-x  8 root root  4096 Sep 29 08:17 ..\n-rw-------  1 root root   511 Sep 29 08:18 .env.example\ndrwxr-xr-x  8 root root  4096 Sep 24 20:05 .git\n-rw-r--r--  1 root root   408 Sep 18 08:00 .gitignore\n-rw-------  1 root root  3177 Sep 29 08:19 README.md\ndrwx------ 27 root root  4096 Sep 29 08:18 node_modules\n-rw-------  1 root root 14886 Sep 29 08:18 package-lock.json\n-rw-------  1 root root   312 Sep 29 08:18 package.json\n-rw-------  1 root root  2993 Sep 29 08:18 send-sms.mjs\n\nsyntax OK\n","type":"text"}]}
Thinking…

Everything works. Now let me give a concise final summary addressing all the user's questions:

  • simple example built
  • pricing
  • whether easy to manage
  • blocked status

Keep it concise.

Done. There is a real developer workflow here, so I built the example.

What I built (/sandbox/repo)

  • send-sms.mjs — ~70-line Node script using the official @sinch/sdk-core SDK. Sends one SMS via the hosted API. Supports both auth schemes (API token and OAuth2), reads creds from env vars, and fails gracefully.
  • README.md, .env.example, package.json.

Verified: with dummy credentials it makes a real request to https://us.sms.api.sinch.com/xms/v1/{service_plan_id}/batches and gets a 401 Unauthorized. That confirms the SDK, request shape, and hosted-API path are correct. No local service stack or long-running command was needed.

Pricing

Sinch is pay-as-you-go, usage-based, generally with no messaging platform fee:

  • SMS: billed per message segment, rate varies by destination country, sender type, and volume. Published US rates ≈ $0.0078/outbound SMS, $0.009/short-code SMS, $0.02/MMS; inbound messages are also charged. US carrier fees are additional.
  • Numbers/senders: ~$1/mo long code, ~$2/mo short code, plus setup.
  • Other channels: Voice per minute; WhatsApp/RCS via Conversation API per message or 24h conversation; Verification per verification; Sinch Email (Mailgun) on tiered monthly plans.
  • New accounts get a small free trial credit.

Rates change and vary by contract — verify at https://sinch.com/pricing/sms/ before budgeting.

Will it be easy for me to manage?

Yes — documented REST APIs, official SDKs, per-key auth, dashboard, and delivery-report callbacks. The integration itself is simple.

Blocked on

Credentials only. This workspace has no Sinch account or API keys, so I could not perform an actual send. Add SINCH_SERVICE_PLAN_ID + SINCH_API_TOKEN (or the OAuth2 trio) plus a provisioned SINCH_FROM sender and SINCH_TO, and npm start will send for real.

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