Insomnia

Insomnia is a developer-facing API testing client — the equivalent of Postman but open-source and backed by Kong. Its value for agents is primarily through the `inso` CLI: running API tests from Insomnia collections or OpenAPI specs in CI/CD pipelines without the desktop app. `inso run test` executes test suites defined in collections; `inso run collection` runs a full request collection; `inso lint spec` validates an OpenAPI spec. Insomnia itself doesn't expose a REST API for external automation — it is the API testing tool, not a programmable service. Best suited for teams using Insomnia collections as their API test artifact. Confidence is docs-derived.

Insomnia collections can store and inject auth: Bearer tokens, OAuth2 (various flows), Basic, Digest, AWS Signature, NTLM, API keys. Environment-specific credentials stored in environments (base environment + sub-environments per deployment stage). Insomnia Cloud Sync (paid): end-to-end encrypted team sync with account auth. `inso` CLI auth: INSOMNIA_API_KEY env var for Insomnia Cloud connectivity. No credential storage outside Insomnia's encrypted local/cloud storage — credentials don't appear in CLI output or logs.

No external REST API. Agent-facing surface is the `inso` CLI (npm install -g insomnia-inso). Commands: `inso run test <suite>` executes test suites (JavaScript test assertions in collection). `inso run collection <collection>` runs all requests in a collection. `inso export spec <document>` exports OpenAPI spec. `inso lint spec <spec>` validates an OpenAPI spec file. Collections defined as `.insomnia` directory (git-sync) or exported JSON/YAML. `inso` exits 0 on pass, 1 on failure — suitable for CI gating. Environment variables injected via --env flag.

CLI exit codes: 0 (pass), 1 (test failure or config error). Test failure output includes test name, status, and assertion error. Network errors reported per-request with HTTP status or connection error. No rate limiting (self-contained local execution). CI integration: standard CI YAML step — run inso, check exit code, publish JUnit XML output (--reporter junit). Insomnia Cloud Sync: uptime at status.insomnia.rest. Self-contained execution (no external service dependency) for local collection runs.

docs.insomnia.rest provides user guide for collection creation, test writing, OpenAPI design, environment configuration, and inso CLI reference. CLI reference documents all subcommands and flags. Getting started requires Node.js for inso CLI. Desktop app free; Insomnia Cloud Sync (team features) is paid. Plugin system (JavaScript) for custom auth and response handling. GitHub Actions examples available. Community via Insomnia GitHub and Discord.