Sourced blog
Writing on OpenAPI, SDKs, and the developer experience.
Posts from the Sourced team on docs migration, SDK generation, API release readiness, and the workflow API teams need from one OpenAPI spec.
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Which SDK generator supports OpenAPI 3.1 webhooks?
A verified table of whether Speakeasy, Stainless, Fern, OpenAPI Generator, and APIMatic generate code from OpenAPI 3.1's webhooks: object, checked 2026-09-16.
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Speakeasy vs Stainless for Python SDKs in 2026
How Speakeasy and Stainless differ for generated Python SDKs: validation approach, async support, free-tier limits, and status after Stainless joined Anthropic. Checked 2026-09-16.
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Scalar vs Bump.sh pricing 2026: the real numbers
Scalar and Bump.sh pricing, fetched directly from each vendor's own pricing page on 2026-09-16 — every tier, price, and limit, with 'Not published' where a vendor doesn't say.
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OpenAPI 3.2.1 (Sept 2026): can path params contain a slash?
OpenAPI 3.2.1, released 2026-09-10, adds explicit spec text: path parameter values with an unescaped slash are never matched. What changed, and what to do about it.
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OpenAPI 3.1 vs Swagger 2.0: should you upgrade first?
If you're still on Swagger 2.0 (OpenAPI 2.0), should you stop at 3.0 or jump straight to 3.1? A decision table built from the actual spec-text differences, verified 2026-09-16.
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How to fix "exclusiveMinimum must be boolean" in OpenAPI
The exclusiveMinimum must-be-boolean error, reproduced with real validators: why a downgraded OpenAPI 3.1 spec fails 3.0 validation, and the exact fix. Tested 2026-09-16.
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How to fix duplicate operationId errors in OpenAPI
Duplicate operationId silently breaks SDK method names and MCP tool names. The spec's uniqueness rule, a reproduced validator error, and the fix, dated 2026-09-16.
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Generate an OpenClaw MCP plugin config from OpenAPI
How to generate an OpenClaw-ready MCP/plugin config from OpenAPI without confusing API connectors with native agent harnesses.
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Generate Hermes MCP config from OpenAPI
How to generate a Hermes-ready MCP server config from OpenAPI, including safe tool filters, local and HTTP transports, and review notes.
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Generate a Grok Bot connector from OpenAPI
How to generate a Grok-ready remote MCP connector from OpenAPI with a hosted endpoint, allowed tools, xAI examples, and a safety report.
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Generate a Claude connector from OpenAPI
How to generate Claude-ready MCP connector files from OpenAPI, with remote setup notes, Desktop fallback, auth review, and safety filters.
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Generate a ChatGPT connector from OpenAPI
How to use OpenAPI to generate a remote MCP connector for ChatGPT and the OpenAI Responses API, with approval settings and safe tool filters.
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OpenAPI to Agent Interface Pack
How to turn an OpenAPI spec into an agent-ready package: MCP server, tool inventory, safety report, host setup files, tests, and a draft PR plan.
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OpenAPI agent-readiness report
What Sourced's agent-readiness report checks before exposing OpenAPI-generated tools to ChatGPT, Grok, Claude, Hermes, OpenClaw, or MCP clients.
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How to generate a Grok Bot MCP server from OpenAPI
A practical guide to generating a Grok Bot MCP server from OpenAPI, including deployment, auth, allowlists, tests, and generated examples.
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Grok Bot API tools safety checklist for OpenAPI
A safety checklist for exposing OpenAPI-generated tools to Grok Bot through remote MCP: allowlists, auth, sensitive reads, write actions, and tests.
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Stainless alternatives for API docs and SDK generation
A practical Stainless alternatives guide for teams comparing Sourced, Speakeasy, Fern, Scalar, Redocly, ReadMe, Bump.sh, GitBook, APIMatic, and OpenAPI Generator.
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Migrate from Speakeasy to Sourced: SDK launch checklist
A practical Speakeasy-to-Sourced migration checklist for API teams that want OpenAPI docs, TypeScript and Python SDK previews, npm/PyPI readiness, and a lighter launch workflow.
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Migrate from Scalar to Sourced: OpenAPI launch checklist
How to evaluate a Scalar-to-Sourced migration for OpenAPI docs, SDK generation, MCP, package publishing, and free hosted review sites.
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Migrate from Redocly to Sourced: governance-to-release checklist
A Redocly-to-Sourced migration guide for teams moving from OpenAPI docs and governance into a unified docs, SDK, npm, PyPI, and release-readiness workflow.
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Migrate from ReadMe to Sourced: developer portal checklist
How to move API docs from ReadMe to Sourced while preserving OpenAPI references, guide content, redirects, SDK examples, custom domains, and search traffic.
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Migrate from GitBook API docs to Sourced
How to move API documentation from GitBook to Sourced while preserving GitBook guides, OpenAPI references, custom domains, redirects, SDK examples, and search traffic.
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Migrate from Bump.sh to Sourced: changelog and SDK checklist
A Bump.sh-to-Sourced migration guide for API docs, OpenAPI changelogs, MCP tools, hosted docs, SDK previews, npm/PyPI readiness, and production cutover.
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Publish a generated TypeScript SDK with npm trusted publishing
How npm trusted publishing fits generated SDK workflows: GitHub Actions OIDC, provenance, package ownership, dry runs, approval gates, and when Sourced should publish.
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How to publish an OpenAPI SDK to PyPI
How to publish an OpenAPI-generated Python SDK to PyPI with trusted publishing, GitHub Actions OIDC, wheels, dry runs, approval gates, and release readiness.
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How to generate an OpenAPI changelog without YAML noise
Generate useful OpenAPI changelogs by ignoring YAML noise, comparing semantic API changes, and routing items through approval.
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Import a Stainless project from GitHub without hunting for files
How a one-click GitHub import should migrate a Stainless project: connect GitHub, pick a repo, detect OpenAPI and stainless.yml, preview SDKs and docs, then approve release steps.
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Free OpenAPI docs hosting before custom-domain launch
How free OpenAPI docs hosting should work: Sourced-hosted noindex review URLs first, then paid indexable custom-domain publishing when you are ready to go live.
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Agent playbook: WYSIWYG editing for generated API docs
A coding-agent guide for combining OpenAPI-generated docs with a WYSIWYG editor for guides, examples, quickstarts, skill files, and release notes.
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Turn OpenAPI into SDKs, docs, and agent tools
A practical guide for turning OpenAPI into TypeScript and Python SDKs, hosted docs, llms.txt, skill files, MCP tools, npm/PyPI readiness, and release approvals.
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Agent prompt pack for API docs and SDK migrations
Copyable prompts for agents migrating API docs, SDK packages, skill files, MCP servers, and OpenAPI workflows to Sourced or a manual stack.
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Agent playbook: migrate from Stainless to Sourced in one pass
A coding-agent playbook for moving a Stainless project to Sourced: inventory OpenAPI, SDK packages, docs, skill files, MCP, and release checks.
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Migrate from Mintlify to Sourced: docs migration checklist
A practical Mintlify-to-Sourced migration guide for API teams moving OpenAPI reference docs, editable guides, llms.txt, MCP, SDK previews, and release readiness into Sourced.
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Migrate from Fern to Sourced: migration checklist
A practical Fern-to-Sourced migration guide for API teams moving OpenAPI docs, SDK packages, MCP or agent outputs, custom domains, and release readiness into Sourced.
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Agent playbook: generate skill files from OpenAPI
How agents should create skill files from OpenAPI using Sourced: auth, workflows, endpoint examples, MCP links, safety rules, and release drift checks.
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Agent playbook: generate an MCP server from OpenAPI
Instructions for coding agents generating MCP servers from OpenAPI, including tool names, schemas, auth, safety notes, install snippets, and Sourced free previews.
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Publishing a TypeScript SDK to npm in 2026
A practical guide to publishing a TypeScript SDK on npm — package.json shape, exports map, dual ESM/CJS, semver discipline, .npmignore, 2FA, and dry-run.
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OpenAPI validator: 5 tools tested in 2026
Five OpenAPI validators compared on real specs: Spectral, Redocly CLI, openapi-cli, swagger-cli, and Sourced. What to ship in CI.
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How to publish an OpenAPI SDK to npm
How to publish an OpenAPI-generated TypeScript SDK to npm: generate, diff, build, dry-run, configure trusted publishing, and ship with provenance.
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Migrating from Stainless to Sourced without losing the SDK experience
What changes (and what doesn't) when you move your OpenAPI workflow off Stainless. A practical walkthrough using the files you already own.
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Generate a TypeScript SDK from OpenAPI: end-to-end in 2026
A practical guide to generating a TypeScript SDK from an OpenAPI spec — spec hygiene, picking a generator, package shape, examples, and publishing. With concrete commands.
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Generate a Python SDK from OpenAPI: end-to-end in 2026
Generate a Python SDK from OpenAPI: spec hygiene, generator choices, packaging, async support, and a practical PyPI workflow.
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DX tools every API company needs in 2026
The DX toolchain for API companies — docs, SDKs, examples, sandbox, status, observability, and agent-readable surfaces — with concrete picks at each tier of growth.
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The developer-experience toolkit for API startups in 2026
What API startups need in DX: docs, SDKs, examples, status, support, telemetry, and one OpenAPI workflow without enterprise pricing.
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Detecting breaking changes in OpenAPI: a 2026 guide
What counts as a breaking change in OpenAPI vs in the generated SDK — concrete rules, the tools that catch them (oasdiff, openapi-diff, Sourced), and how to wire detection into CI.
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The API launch checklist (with templates)
A practical pre-launch checklist for a public API in 2026: spec hygiene, SDKs, docs, examples, status page, changelog, rate limits, auth, support, and what to monitor on day one.
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Generate an SDK from OpenAPI in five minutes
Upload an OpenAPI 3.x spec, get a typed TypeScript and Python SDK preview with a runnable example. Step-by-step, with what's in the output.
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Stainless is joining Anthropic. What it means for your SDK and docs
What changes (and what doesn't) for Stainless customers after the Anthropic acquisition. The questions to ask, the files to inventory, and what a reversible migration looks like.
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How to evaluate API documentation tools without getting locked in
A practical buyer's lens for picking API docs tooling: OpenAPI fidelity, SDK examples, llms.txt, migration risk, and pricing transparency. The criteria buyers actually use.
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OpenAPI vs stainless.yml: what each file actually controls
OpenAPI defines the API. stainless.yml defines the SDK. Most migration confusion comes from mixing the two. A field-by-field walkthrough.
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llms.txt: the quietest SEO win for API docs in 2026
What llms.txt is, why agent-readable docs matter for API teams, and how to ship it from an OpenAPI spec without rewriting your docs site.
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SDK compatibility reports: the diff that makes migrations reversible
What's in a generated-SDK compatibility report, why teams skip it, and how to read one when the stakes are a published package.
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Swagger vs OpenAPI: what changed, what didn't, and what to use in 2026
Swagger and OpenAPI mean different things in practice. A short guide to the names, the actual specification, and what your team should standardize on today.
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Examples of great API documentation (and what to copy from them)
Six docs sites worth studying — Stripe, Twilio, Linear, GitHub, Plaid, Anthropic — with the specific design choices that make each one work.
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REST API versioning best practices for teams shipping SDKs
Versioning strategies that actually work in 2026 — URL path, header, query, content negotiation. With trade-offs and what to pick for a public API.
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OpenAPI best practices for SDK-friendly specs
The OpenAPI patterns that produce idiomatic SDK code — naming, schema reuse, examples, security. Practical, with what to do and what to avoid.
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OpenAPI 3.1 vs 3.0: which to use in 2026
OpenAPI 3.1 vs 3.0: the five real differences, when to use each, how to upgrade, and how to downgrade 3.1 to 3.0 safely — with a tested worked example.
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REST vs GraphQL: which one do you need in 2026?
A practical guide to choosing between REST and GraphQL for a new API in 2026. Where each one shines, where each one bites, and what to pick for typical SaaS use cases.
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Swagger Codegen vs modern SDK generators: what changed, what to use
Swagger Codegen and OpenAPI Generator built the SDK-from-spec category. Where they still fit, where modern alternatives win, and a practical decision tree for 2026.
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OpenAPI security best practices for production APIs
How to model auth, secrets, scopes, and audit-friendly behavior in OpenAPI 3.x. Practical patterns for API keys, OAuth, mTLS, and the gotchas that bite in production.
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OpenAPI webhooks: the right pattern in 3.1
How to model webhooks in OpenAPI 3.1, why the 3.0 callbacks workaround was awkward, and what generated SDKs and docs should do with webhook definitions.
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What is an MCP server? A practical introduction
MCP (Model Context Protocol) lets AI agents call your API as a typed tool. What an MCP server is, what it isn't, and how to think about shipping one for your product.
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MCP server security: what to lock down before shipping
MCP servers expose tools to AI agents. Auth, sandboxing, rate limits, audit logs — the security checklist before exposing internal capabilities to an LLM client.
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Generate an MCP server from OpenAPI
How to generate an MCP server from OpenAPI: map operations to tools, convert schemas to arguments, handle auth, mark destructive actions, and review the tool surface.
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OpenAPI codegen: tools, SDK output, and mistakes to avoid
OpenAPI codegen explained: how generators turn specs into SDKs, how to pick a tool, and the spec patterns that create bad generated code.