Captions

Fair

Agent Native Score

Free TierAPI Key Auth

An AI-powered video captioning and subtitle generation platform that automatically creates accurate captions for video content. It provides APIs and tools for developers to integrate automated captioning into their applications.

Categories: Media · Ai Apis

#3 of 32 in Media · #19 of 69 in Ai Apis

Checklist Breakdown

15 of 33 checks passed. 14 unscored.

Discovery 50%

Can an agent find and understand this tool without a web search?

✗ Published OpenAPI/Swagger spec

✗ Has llms.txt or llms-full.txt

✗ Has an MCP server (official or well-maintained)

✗ MCP server listed in a public registry

✓ API reference docs are publicly accessible

✓ Docs include runnable code examples

✓ Has a public changelog or release notes

✓ Has a public status page

Auth & Onboarding 100%

Can an agent create an account and get credentials without human intervention?

✓ Signup does not require CAPTCHA

✓ Signup does not require phone verification

✓ Supports API key auth (not only OAuth)

✓ API key obtainable without manual approval

✓ No mandatory billing info to start

✓ Can sign up without creating an organization

Pricing 100%

Can an agent operate autonomously without upfront payment or contracts?

✓ Has a free tier

✓ Usage-based pricing available

✓ No minimum contract or commitment

✓ Pricing page is public (no 'contact sales')

✓ Free tier sufficient for testing (not just a trial)

Agent Tooling Not yet scored

How well does the API work for non-human consumers?

— SDK available in 2+ languages

— Structured error responses (JSON with error codes)

— Idempotency support on write endpoints

— Pagination on list endpoints

— Webhook/event support

— Sandbox or test mode available

— Rate limit headers in responses

— Consistent REST resource naming

Reliability Not yet scored

Does the tool fail gracefully when an agent makes a mistake?

— Meaningful error messages (not just 500)

— 429 responses include Retry-After header

— Documented uptime SLA (99.9%+)

— Graceful degradation under rate limits

— Request IDs in responses for debugging

— API versioning supported

Reviewer Notes

Captions lacks MCP server, OpenAPI spec, and llms.txt documentation, making discovery challenging for agents. While it offers API access with key-based authentication and a free tier enabling autonomous operation, the absence of structured API documentation and no public sandbox environment limits agent tooling capabilities. The platform appears stable with OAuth and API key support, but without formal OpenAPI specs, agents cannot reliably understand available endpoints and response schemas.

Captions

Let your agents find tools like Captions