Insomnia alternatives
The highest-scoring alternative to Insomnia is Checkly at 85/100 on the AgentReady, against 62/100 for Insomnia.
All scored in API Testing & Monitoring.
What Checkly does that Insomnia does not
Checkly passes llms.txt published, openapi / spec quality, authentication documented, request examples provided, response examples provided, errors and status codes documented, limits / constraints documented, self-service signup, programmatic credential creation, fast time to first request, copyable quickstart, machine-readable errors, retry behavior documented, rate-limit behavior predictable, and Insomnia fails them. That is the whole of the gap between the two scores, so if none of those matter to your agent the ranking above overstates the difference.
Why people look for an alternative
Insomnia fails llms.txt published, llms-full.txt / full agent docs, openapi / spec quality, authentication documented, request examples provided, response examples provided, errors and status codes documented, limits / constraints documented, self-service signup, no mandatory sales call, programmatic credential creation, fast time to first request, copyable quickstart, machine-readable errors, retry behavior documented, idempotency support, rate-limit behavior predictable. Each one is a place an unattended run stops, which is usually what sends someone looking in the first place.
Where Insomnia loses the points
| Pillar | Insomnia | What it measures |
|---|---|---|
| Discover | 87 | Can an agent find it at all: sitemap, robots, structured data. |
| Understand | 38 | Is there a spec, an llms.txt, a machine-readable description. |
| Adopt | 55 | Signup, keys, SDKs, and whether a human has to be involved. |
| Operate | 67 | Rate-limit headers, errors, status, and behaviour under load. |
Insomnia is weakest on understand at 38/100. Without a spec an agent has to guess at endpoints, and it guesses wrong. If that is the part your agent depends on, take the ranking above seriously; if it is not, Insomnia may still be the right pick.
What an agent runs into with Insomnia
These are the findings from the last audit on 2026-08-25. Each one is a place unattended software stops, which is the practical reason to look at the list above.
- Make signup self-serve; an agent cannot sit through a sales call.
- Flesh out the OpenAPI: paths, schemas, and descriptions.
- Document error responses as an enum in your OpenAPI.
- Let agents create API keys programmatically.
- Return X-RateLimit / Retry-After headers so agents pace themselves.
- Add /llms.txt so agents can find and read your capabilities.
- Publish an AGENTS.md or llms-full.txt with full agent context.
- Add request examples to your API reference.
What this category actually supports
Across the 9 products scored in API Testing & Monitoring, monitor an api is offered by 89%, test an api is offered by 67%.
An agent can get this list directly: resolve("alternative to Insomnia") over the MCP server, or GET /v1/categories/api-testing.