# Finnhub — API Agent Score

> Score: 75/100 (Grade: B) | Domain: finnhub.io | Rubric: 1.0.0 | Checked: July 24, 2026

Finnhub scored 75/100 (B), classified "partially-ready".

[View full report](https://www.postman.com/ai/ai-ready-apis/company/finnhub)
[All organizations](https://www.postman.com/ai/ai-ready-apis/llms.txt)

## Summary

- Overall: 75/100 (B)
- Classification: partially-ready

## Category Scores

- API Design: 100/100 (A+)
- Developer Experience: 100/100 (A+)
- Agent Discovery: 69/100 (C)
- Agent Understanding: 68/100 (C)
- Agent Usability: 56/100 (D)

## Check Results

### API Design

- [pass] Machine-readable, versioned contract — Versioning declared (info.version="1.0.0") and url-versioning detected. Investigated: spec 100%, docs 100%.
- [pass] Schema coverage & depth — 247/247 (100%) public params are fully typed (no any/**kwargs). Analyzer confirms all methods have a derivable input schema. Investigated: sdk 100%, spec 83%.
- [pass] Auth declared & discoverable — Authentication required (global or on every operation). Investigated: spec 100%, docs 100%.
- [pass] Security & governance hygiene — No credential-shaped strings detected in spec. Investigated: spec 100%, wellknown 50%.
- [pass] Example coverage — README is present and includes a runnable quickstart. Investigated: sdk 100%, spec 0%.

### Developer Experience

- [pass] Self-service developer portal — Signup page at https://finnhub.io/; no free-tier language detected in docs/pricing. Investigated: docs 100%.
- [pass] Quickstart present — Quickstart at https://finnhub.io/docs/api/quickstart with a runnable first-call sample. Investigated: docs 100%.
- [pass] Description completeness — 83% description completeness (target 90%+). Investigated: spec 100%, sdk 100%.
- [pass] Changelog published — Newest official SDK activity 30 day(s) ago. Investigated: sdk 100%, spec 0%, docs 0%.
- [skip] Code samples in docs — No surface produced evidence for this capability in this run.

### Agent Discovery

- [pass] Registry & SDK presence — Indexed on Context7 (finnhub-stock-api/finnhub-js, 239 snippets). Investigated: docs 100%, sdk 100%, cli 0%.
- [warn] Docs reachable, not hard auth-gated — 1 of 1 pages return 200 for non-existent URLs (soft 404). Investigated: docs 50%.
- [warn] llms.txt present, valid & comprehensive — No llms.txt found at any candidate location (https://finnhub.io/docs/api/llms.txt, https://finnhub.io/llms.txt, https://finnhub.io/docs/llms.txt). Investigated: docs 33%, sdk 0%.
- [warn] Crawlable / AEO — Sitemap present (0 entries) but carries no lastmod values. Investigated: wellknown 75%.

### Agent Understanding

- [pass] Operation purpose clarity — 93% of operations have a clear summary + operationId an agent can select on. Investigated: spec 100%.
- [warn] Machine-readable errors (RFC 9457) — Single base error "null" present, but only 1 subclass found; a richer hierarchy lets consumers catch narrowly. Investigated: sdk 50%, spec 0%, docs 0%.
- [warn] Agent-navigable, token-efficient docs — 1 of 1 pages appear to be client-side rendered SPA shells (root detected); agents using HTTP fetches will see no content. Investigated: docs 57%.
- [fail] Agent instructions file (AGENTS.md) — No AGENTS.md at the site root or /.well-known/. Investigated: wellknown 0%.
- [skip] Docs structured data — No surface produced evidence for this capability in this run.
- [skip] Description consistency across surfaces — Only 0 surface description(s) with ≥6 tokens available; need at least 2 to compare.

### Agent Usability

- [pass] Pagination documented & consistent — Pagination params detected on 19 list endpoint(s). Investigated: docs 100%, spec 75%.
- [pass] Sandbox separation — Sandbox environments are exposed (sandbox). Investigated: sdk 100%, spec 0%, docs 0%.
- [fail] Idempotency documented — 0% of mutating operations document idempotency. Investigated: spec 0%, docs 0%, sdk 0%.
- [fail] Rate-limit signaling — No rate-limit response headers documented. Investigated: spec 0%, docs 0%.
- [fail] Runnable collection with test scripts — No public Postman workspace discovered for the org. Investigated: platform 0%.

## Executive Summary

Finnhub's API program shows strength in basic discoverability but has two critical gaps that put partner and agent integrations at risk. The absence of machine-readable agent instructions and a lack of runnable, tested collections mean AI agents cannot reliably interpret the API's intent or validate their integrations without guesswork. Closing these gaps — alongside tightening operational reliability signals like rate-limit signaling and idempotency documentation — should be the immediate priority to unlock self-serve partner success and agent-driven workflows.