docs: document namespace prefix syntax for endpoint references

[devin-ai-integration]

Summary

Documents the namespace::METHOD /path syntax for endpoint references when using namespaces (multiple API specs). This is relevant wherever endpoints are specified in METHOD /path format — for example, payments::POST /oauth/token instead of POST /oauth/token.

Files changed (10):

• OAuth auth config (auth.mdx): Added <Tip> callout in the OAuth client credentials accordion
• OAuth snippets (oauth-get-token.mdx, oauth-refresh-token.mdx): Updated endpoint ParamField descriptions
• API Reference layout (customize-api-ref.mdx): Added namespace example in the OpenAPI "Ordering top-level sections" tab
• Component docs (endpoint-request-snippet.mdx, endpoint-response-snippet.mdx, endpoint-schema-snippet.mdx, runnable-endpoint.mdx): Updated endpoint ParamField descriptions
• OpenAPI spec settings (openapi-specs.mdx): Updated settings.filter.endpoints ParamField description
• Project structure (project-structure.mdx): Added link from "Add namespaces" step to the generators.yml reference for configuration details

Additionally, endpoint-schema-snippet.mdx was missing a Properties section entirely — one was added with endpoint and selector param documentation alongside the namespace info.

Updates since last revision

• All namespace links now point to the project structure page instead of the generators.yml reference page. The project structure page's "Add namespaces" step links back to generators.yml#namespace for configuration details.
• Standardized all example namespace names to payments (previously a mix of iam and myapi) for consistency with the project-structure page's payments-api example.

Review & Testing Checklist for Human

• Verify the #combined-sdks-from-multiple-apis anchor resolves correctly on the project-structure page. All namespace links across 9 files now point to this anchor. If the heading slug doesn't match, every link will be broken.
• Verify the #namespace anchor exists on the generators-yml reference page (/learn/sdks/reference/generators-yml#namespace). The project-structure page now links there from the "Add namespaces" step.
• Review the new Properties section added to endpoint-schema-snippet.mdx — this is additive beyond just namespace docs. Confirm the selector values listed (request, request.path, request.query, request.body, response, response.body) are accurate and complete.
• Spot-check that payments is used consistently as the example namespace name across all changed files. Previously a mix of iam and myapi was used; verify no stale references remain.
• Check rendered output on the preview deployment — click through namespace links from at least 2-3 of the changed files to confirm they land on the correct section of the project-structure page.

Suggested test plan: Open the preview deployment, navigate to the OAuth auth config page, click the namespace link in the Tip callout, and verify it lands on the "Combined SDKs from multiple APIs" section of the project-structure page. From there, verify the "Add namespaces" step links to the generators.yml reference. Repeat for one component doc page (e.g., endpoint-request-snippet). Grep the diff for iam:: and myapi:: to confirm no stale namespace names remain.

Notes

• Two files (oauth-get-token.mdx, oauth-refresh-token.mdx) had missing trailing newlines which were incidentally fixed.
• Requested by: Fern Support
• Link to Devin run

[devin-ai-integration]

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🌿 Preview your docs: https://fern-preview-ae297c3c-8964-4f2e-b4db-bc18bdfc4385.docs.buildwithfern.com/learn

Here are the markdown pages you've updated:

• learn/api-definitions/openapi/authentication
• learn/api-definitions/overview/project-structure
• learn/docs/api-references/customize-api-reference-layout
• learn/docs/writing-content/components/request-snippet
• learn/docs/writing-content/components/response-snippet
• learn/docs/writing-content/components/endpoint-schema-snippet
• learn/docs/writing-content/components/runnable-endpoint