Antigravity workflow

API testing for Google Antigravity

Give Google Antigravity runnable Markdown API specs, Reqbook skills, and MCP tools for testing endpoints without rediscovering backend contracts.

Install Reqbook Read the MCP API testing guide

Give Antigravity an executable API layer

Antigravity can inspect a codebase and operate development tools, but API work becomes expensive when every task starts by scanning routers, schemas, authentication middleware, and old request examples. Reqbook keeps the contract in api-docs/*.md, where Antigravity can read the exact endpoint shape and run the same artifact.

Focused context

Search one endpoint contract instead of loading a large backend into the agent context window.

Executable specs

Run requests, assertions, variables, and multi-step flows from reviewable Markdown files.

Shared workflow

Developers, CI, the local browser UI, and Antigravity use the same API source of truth.

Install Reqbook skills and MCP for Antigravity

Install the Reqbook binary, initialize the API workspace, then register the embedded skill and MCP server specifically for Antigravity. 

$ curl -fsSL https://markapidown.net/install.sh | sh
$ rqb init --name=my-api --dev-url=http://localhost:8080 --yes
$ rqb skills install --agent=antigravity
$ rqb install mcp --agent=antigravity
  • The Reqbook skill is installed under the agent skills directory in the project.
  • The MCP configuration is written to ~/.gemini/antigravity/mcp_config.json.
  • Restart or reload Antigravity after installing MCP so the new Reqbook tools are discovered.
  • Run rqb doctor --fix after upgrading Reqbook to refresh stale skills.

A practical Antigravity API testing loop

Start from the contract, execute the endpoint, and diagnose failures before asking the agent to scan implementation details. This keeps the first pass small and gives Antigravity structured evidence for the next code change. 

$ rqb context refunds.quote --mode surgical --brief \
  --max-fields 12 --include variables,request,response,errors,rules,verify
$ rqb exec api-docs/apis/refunds/post-quote.md
$ rqb diagnose api-docs/apis/refunds/post-quote.md --output json
$ rqb validate api-docs/

When the endpoint behavior changes, update its Markdown contract in the same pull request. The resulting diff explains the request, expected response, and verification rules to both reviewers and future agent sessions.

When this workflow is a good fit

Use Reqbook with Antigravity when API behavior should remain local, versioned, executable, and visible during code review. It is especially useful for backend changes, integration debugging, onboarding flows, and repeated API tasks where rediscovering request details would waste agent context.

Explore the broader agent-native API workspace, review API testing for coding agents, or install Reqbook from the CLI release channels.