Capsule

39
Fair
Agent Native Score
Free TierAPI Key AuthOpenAPI Spec

Capsule is a web-based CRM platform designed for small businesses and sales teams to manage contacts, leads, and customer relationships. It provides tools for contact management, sales pipeline tracking, and customer communication.

Categories: Crm · Sales · Contacts
#12 of 66 in Crm · #5 of 38 in Sales
Checklist Breakdown

13 of 33 checks passed. 14 unscored.

Discovery 63%

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 50%

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

Capsule has a functional REST API with OAuth2 and API key support, which helps with discovery and authentication, but lacks an MCP server and llms.txt file. The main weakness is account creation — new accounts require manual signup through their web interface with no programmatic registration API, blocking fully autonomous agent onboarding. The API documentation exists but isn't comprehensive enough for complex operations. Strengths include a free tier for testing and reasonable rate limits. Reliability is moderate; the service is stable but error messages could be more detailed for agent troubleshooting.

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