# Alpaca — API Agent Score

> Score: 87/100 (Grade: A) | Domain: alpaca.markets | Rubric: 1.0.0 | Checked: July 24, 2026

Alpaca scored 87/100 (A), classified "ai-ready".

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

## Summary

- Overall: 87/100 (A)
- Classification: ai-ready

## Category Scores

- API Design: 84/100 (A)
- Developer Experience: 75/100 (B)
- Agent Discovery: 91/100 (A+)
- Agent Understanding: 84/100 (A)
- Agent Usability: 96/100 (A+)

## Check Results

### API Design

- [pass] Auth declared & discoverable — Authentication required (global or on every operation). Investigated: spec 100%, docs 100%.
- [warn] Machine-readable, versioned contract — info.version="1.1.1" set but no versioning scheme (URL / header / media type) detected. Investigated: spec 75%, docs 50%.
- [warn] Schema coverage & depth — Medium parameter complexity (avg 1.8 params/op; nested/body schemas present). Investigated: spec 72%, sdk 60%.
- [warn] Security & governance hygiene — 4 credential-shaped strings detected in spec: aws-access-key (×4). Investigated: spec 67%, wellknown 50%.
- [pass] Example coverage — README is present and includes a runnable quickstart. Investigated: sdk 100%, spec 0%, docs 0%.

### Developer Experience

- [pass] Self-service developer portal — Signup page at https://alpaca.markets/signup; no free-tier language detected in docs/pricing. Investigated: docs 100%.
- [pass] Description completeness — 85% description completeness (target 90%+). Investigated: spec 100%, sdk 0%.
- [pass] Changelog published — changelog documented in the docs site at https://docs.alpaca.markets/us/changelog. Investigated: spec 100%, docs 100%, sdk 100%.
- [warn] Quickstart present — Quickstart page reachable (12 variants scanned starting at https://docs.alpaca.markets/us/docs/getting-started) but no runnable code sample detected in HTML or .md variant. Investigated: docs 50%.
- [fail] Code samples in docs — No detectable code samples across 20 sampled docs pages. Investigated: docs 0%.

### Agent Discovery

- [pass] Docs reachable, not hard auth-gated — All 50 sampled pages are publicly accessible. Investigated: docs 100%.
- [pass] Registry & SDK presence — Indexed on Context7 (alpacahq/alpaca-py, 985 snippets). Investigated: docs 100%, cli 100%, sdk 67%, mcp 0%, wellknown 0%.
- [warn] llms.txt present, valid & comprehensive — llms.txt is 126,895 characters (exceeds 100,000 threshold; will be truncated by most agents). Investigated: docs 86%, sdk 0%.
- [warn] Crawlable / AEO — No sitemap discoverable via robots.txt or /sitemap.xml on the docs host. Investigated: wellknown 50%.

### Agent Understanding

- [pass] Machine-readable errors (RFC 9457) — 9 distinct 4xx/5xx response codes documented. Investigated: docs 100%, sdk 100%, spec 50%.
- [pass] Operation purpose clarity — 99% of operations have a clear summary + operationId an agent can select on. Investigated: spec 100%.
- [warn] Agent-navigable, token-efficient docs — 4 of 50 pages between 50K–100K chars (max 90K). Investigated: docs 90%.
- [pass] Docs structured data — JSON-LD Article markup on 18/18 assessed pages (100%) with dateModified present. Investigated: docs 100%.
- [warn] Description consistency across surfaces — Mean pairwise description similarity across 3 surfaces (spec, docs, sdk) is 3% (threshold 35% for full credit).
- [fail] Agent instructions file (AGENTS.md) — No AGENTS.md at the site root or /.well-known/. Investigated: wellknown 0%.

### Agent Usability

- [pass] Idempotency documented — idempotency documented in the docs site at https://docs.alpaca.markets/us/reference/post-v1-instant-funding. Investigated: spec 100%, docs 100%, sdk 100%.
- [pass] Rate-limit signaling — 3 distinct rate-limit response headers documented. Investigated: spec 100%, docs 100%.
- [pass] Pagination documented & consistent — Pagination params detected on 25 list endpoint(s). Investigated: spec 100%, docs 100%.
- [pass] Sandbox separation — sandbox documented in the docs site at https://docs.alpaca.markets/us/docs/getting-started-with-broker-api. Investigated: spec 100%, docs 100%, sdk 100%.
- [warn] Runnable collection with test scripts — No test scripts found in the workspace's collections. Investigated: platform 50%.

## Executive Summary

Alpaca's API program shows strong fundamentals across design, discoverability, and usability — partners and agents can find and call your APIs with confidence. The two areas that need immediate attention are agent-facing context and developer onboarding: there is no structured instructions file to tell AI agents how to navigate or use the API, and the documentation lacks inline code samples that let partners get to a working integration without leaving the docs. Closing these two gaps will meaningfully accelerate partner activation and make Alpaca's API surface fully legible to the coding agents that partners increasingly rely on.