The Chicago Signal

Developers

The Chicago Signal developer docs

The full documented surface. Everything here is public and free to use within the rules below.

OpenAPI document

The complete machine-readable spec is at /openapi.json (also served at /api/openapi.json) — OpenAPI 3.1, every operation typed, every error shape documented.

Endpoints

Content access

Every guide is available as HTML at its normal URL, or as plain Markdown by sending Accept: text/markdown — the response carries Vary: Accept so caches don't mix the two up. /llms.txt lists every indexable guide in one file.

Errors

Every error response on this site shares one shape: { error, code, message, hint, status, docs }, plus retryAfter on a 429. error is a plain string kept stable for the site's own forms; code is the field to match on programmatically.

Rules

Read and cite what's here freely. Don't submit an email address to /api/subscribe that isn't your own or one you have permission to sign up — that sends a real welcome email. Robots.txt reserves this site from AI training while welcoming search and reference crawling; see /robots.txt.

Questions

Not covered here? Contact us.