# Lob — API Agent Score

> Score: 66/100 (Grade: C) | Domain: lob.com | Rubric: 1.0.0 | Checked: July 29, 2026

Lob scored 66/100 (C), classified "partially-ready".

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

## Summary

- Overall: 66/100 (C)
- Classification: partially-ready

## Category Scores

- API Design: 76/100 (B)
- Developer Experience: 59/100 (D)
- Agent Discovery: 65/100 (C)
- Agent Understanding: 62/100 (C)
- Agent Usability: 66/100 (C)

## Check Results

### API Design

- [warn] Machine-readable, versioned contract — info.version="1.0.0" set but no versioning scheme (URL / header / media type) detected. Investigated: spec 81%, docs 63%.
- [warn] Schema coverage & depth — 0/24 (0%) enum-like params are realized as constrained types (not bare strings). Investigated: sdk 78%, spec 71%.
- [pass] Security & governance hygiene — No credential-shaped strings detected in spec. Investigated: spec 100%, wellknown 0%.
- [pass] Example coverage — 62% example coverage (target 80%+). Investigated: spec 100%, docs 100%, sdk 100%.
- [warn] Auth declared & discoverable — No securitySchemes declared. Investigated: docs 25%, spec 13%.

### Developer Experience

- [pass] Code samples in docs — Code samples in 10 language(s) across docs (top: shell, curl, typescript); 1/1 pages have ≥ 2 languages on the same page. Investigated: docs 100%.
- [pass] Description completeness — 17% description completeness. Investigated: spec 100%, sdk 100%.
- [pass] Changelog published — Newest official SDK activity 9 day(s) ago. Investigated: sdk 100%, spec 0%, docs 0%.
- [fail] Self-service developer portal — Signup page is sales-gated (contact-sales/request-access language detected). Investigated: docs 0%.
- [fail] Quickstart present — No quickstart/getting-started page found at the conventional paths. Investigated: docs 0%.

### Agent Discovery

- [pass] Registry & SDK presence — Indexed on Context7 (websites/help_lob_developer-docs, 181 snippets). Investigated: docs 100%, sdk 67%, cli 0%.
- [warn] Docs reachable, not hard auth-gated — Server ignores Accept: text/markdown header (0/1 pages return markdown). Investigated: docs 75%.
- [warn] Crawlable / AEO — No sitemap discoverable via robots.txt or /sitemap.xml on the docs host. Investigated: wellknown 50%.
- [fail] llms.txt present, valid & comprehensive — No llms.txt found at any candidate location (https://docs.lob.com/llms.txt, https://docs.lob.com/docs/llms.txt). Investigated: docs 0%, sdk 0%.

### Agent Understanding

- [pass] Machine-readable errors (RFC 9457) — No 4xx/5xx response codes (or default error response) documented anywhere in the spec. Investigated: docs 100%, sdk 100%, spec 50%.
- [warn] Operation purpose clarity — 21% of operations are agent-inferable. Investigated: spec 50%.
- [warn] Agent-navigable, token-efficient docs — No pages support .md URLs (0/1 tested). Investigated: docs 50%.
- [warn] Description consistency across surfaces — Mean pairwise description similarity across 2 surfaces (spec, docs) is 2% (threshold 35% for full credit).
- [fail] Agent instructions file (AGENTS.md) — No AGENTS.md at the site root or /.well-known/. Investigated: wellknown 0%.
- [fail] Docs structured data — Neither JSON-LD nor OpenGraph/meta tags detected across 1 assessed pages (1 JS-rendered). Investigated: docs 0%.

### Agent Usability

- [pass] Idempotency documented — Built-in retry machinery is present (grep-derived). Investigated: sdk 100%, spec 0%, docs 0%.
- [pass] Sandbox separation — Test credentials signaled (test-key prefixes) but no sandbox server declared in spec. Investigated: spec 100%, docs 100%, sdk 100%.
- [warn] Rate-limit signaling — No rate-limit response headers documented. Investigated: spec 25%, docs 25%.
- [warn] Runnable collection with test scripts — No test scripts found in the workspace's collections. Investigated: platform 50%.
- [fail] Pagination documented & consistent — 2 list endpoint(s) exist but no pagination params found. Investigated: spec 0%, docs 0%.

## Executive Summary

Lob's API Design is a relative strength — the contract is machine-readable and auth is well-defined, giving partners a solid technical foundation. The critical gaps are in discoverability and agent understanding: there is no llms.txt, no agent instructions file, and no structured data in docs, which means AI agents cannot reliably find, parse, or act on Lob's APIs without human intervention. Equally urgent is the developer onboarding experience, where the absence of a self-service portal and quickstart guide forces partners into slow, manual processes before they can make a single call. Prioritize surfacing a discoverable, agent-ready documentation experience first, then close the onboarding gap so partners reach their first successful integration in minutes.