Agent-Based API Test Generation
Overview
Keploy Enterprise supports agent-based test generation, allowing AI coding assistants (Claude Code, Cursor, Antigravity, GitHub Copilot) to generate and iterate on API tests directly in your IDE.
Instead of switching to a separate web UI, the agent:
- Generates test YAML using the Keploy test format
- Runs tests via Keploy Enterprise with structured JSON output
- Reads coverage gaps from the output and generates targeted tests
- Syncs results to the Keploy platform for team-wide visibility
The Keploy platform automatically builds and refines the API schema over time from your test runs, so providing an OpenAPI spec upfront is optional.
Prerequisites
- Keploy Enterprise installed (installation guide)
- A running API server to test against
- An OpenAPI spec (optional; the platform generates schema coverage over time)
Setup for AI Agents
To teach your AI agent the Keploy test format, add a context file to your project root. The agent reads this file and learns how to generate valid test suites.
Claude Code
Create a CLAUDE.md file in your project root with the Keploy test format reference. Claude Code automatically reads project-level markdown files. The file should document:
- The YAML test suite schema (name, description, steps)
- Available assertion types (status_code, json_equal, json_contains, etc.)
- Variable extraction and substitution rules
- The CLI commands to run and validate tests
See the Test Suite YAML Format section below for the complete schema to include.
Cursor
Create a .cursorrules file in your project root with the same test format reference.
Antigravity
Use the same test format documentation as system instructions or project context.
MCP Server (Recommended for AI Agents)
Keploy provides an MCP (Model Context Protocol) endpoint that gives AI agents native tool access to the Automated Test Generation (ATG) platform. Instead of the agent parsing CLI output, it calls structured tools directly and gets typed JSON responses. The CLI workflow described later on this page is an alternative for environments where MCP is not available.
The MCP endpoint is built into the Keploy API server at /client/v1/mcp. Tools are auto-generated from the OpenAPI spec—when the API evolves, tools update automatically.
Available Tools
| Tool | What it does |
|---|---|
listApps | List all applications |
createApp | Create a new application |
generateTestSuites | Trigger AI test generation from an OpenAPI spec |
runTestSuites | Execute test suites against a target API |
listTestSuites | List test suites for an app |
createTestSuite | Create a test suite from steps JSON |
listAppsWithRecordings | List apps that have integration test recordings from Keploy |
listRecordings | List recording sessions (test sets) for an app |
getRecording | Get recorded HTTP request/response pairs and dependency mocks |
getGeneratedSchema | Get the auto-generated OpenAPI schema from captured traffic |
generate_and_wait | Generate tests and wait for completion (composite) |
run_and_report | Run tests and return results with failures and coverage gaps (composite) |
get_coverage_gaps | Get uncovered endpoints with prioritized suggestions |
| ...43+ API tools | Every /client/v1 endpoint is available as an MCP tool |
The examples below include an API key in configuration files. Do not commit API keys to version control. Use environment variables or add the config file to .gitignore. For CI/CD, use secret management.
The examples below use the Keploy Cloud URL (https://api.keploy.io). If you're self-hosting, replace it with your own API server address.
MCP Client Configuration
Claude Code
Add to your Claude Code MCP settings (~/.claude.json or project-level). Note: Claude Code requires the type: http field for StreamableHTTP transport (other clients do not need it).
{
"mcpServers": {
"keploy": {
"type": "http",
"url": "https://api.keploy.io/client/v1/mcp",
"headers": {
"Authorization": "Bearer kep_YOUR_API_KEY"
}
}
}
}
Then ask Claude Code:
"Use the Keploy MCP tools to generate API tests for my OpenAPI spec, run them against my staging server, and show me coverage gaps"
Claude Code will call generate_and_wait, run_and_report, and get_coverage_gaps tools directly.
Cursor
Cursor supports MCP servers. Add to your Cursor MCP configuration (.cursor/mcp.json):
{
"mcpServers": {
"keploy": {
"url": "https://api.keploy.io/client/v1/mcp",
"headers": {
"Authorization": "Bearer kep_YOUR_API_KEY"
}
}
}
}
Cursor's AI agent can then discover and use all Keploy tools natively.
GitHub Copilot
GitHub Copilot supports MCP in agent mode. Add to .github/copilot-mcp.json in your project (add this file to .gitignore since it contains credentials).
Note: GitHub Copilot uses the top-level key
servers(notmcpServersas other clients use). This is Copilot-specific.
{
"servers": {
"keploy": {
"url": "https://api.keploy.io/client/v1/mcp",
"headers": {
"Authorization": "Bearer kep_YOUR_API_KEY"
}
}
}
}
Antigravity
Antigravity (formerly Windsurf) supports MCP servers. Add to your Antigravity MCP settings. Note: Antigravity uses serverUrl (not url) for the endpoint field.
{
"mcpServers": {
"keploy": {
"serverUrl": "https://api.keploy.io/client/v1/mcp",
"headers": {
"Authorization": "Bearer kep_YOUR_API_KEY"
}
}
}
}
How it Works
- The agent discovers available tools via the MCP
tools/listmethod - When you ask "generate API tests", the agent calls
generate_and_waitwith your OpenAPI spec - The tool triggers AI generation on the Keploy platform, polls until complete, and returns the created suites
- The agent calls
run_and_reportto execute suites against your API - The tool returns pass/fail results, assertion failures, and coverage gaps
- The agent reads the coverage gaps and generates additional test suites for uncovered endpoints
- This loop continues until coverage targets are met
Using Recorded Traffic for Better Tests
If you use Keploy's integration testing (k8s-proxy or local agent), recorded HTTP traffic is available to AI agents via MCP. This produces higher-quality test suites because the AI can reference real request/response patterns instead of guessing from the OpenAPI spec alone.
Agent workflow:
1. listAppsWithRecordings → find apps with real traffic data
2. listRecordings → browse recording sessions
3. getRecording → get actual HTTP request/response pairs + dependency mocks
4. getGeneratedSchema → get the OpenAPI spec auto-generated from traffic
5. generate_and_wait (with examples from step 3) → produce realistic test suites
Ask your agent:
"Use the Keploy MCP tools to find apps with recorded traffic, fetch the recordings, and use them as examples to generate comprehensive API tests"
The MCP endpoint uses the same API key as the REST API and accepts the same two authentication methods. The examples above use Authorization: Bearer kep_..., but you can also use X-API-Key: kep_... as an alternative (replace the Authorization header with "X-API-Key": "kep_YOUR_API_KEY" in the config). See the Public API docs for details. All tools proxy to /client/v1 endpoints using the caller's credentials.
Workflow
1. Initialize the test directory
keploy test-gen init --dir ./keploy
This creates:
keploy/tests/example.yaml—a working example test suitekeploy/keploy-runner.yaml—a configuration reference template
2. Generate tests with your AI agent
Ask your agent to generate tests:
"Generate API tests for my user CRUD endpoints"
The agent writes YAML test files directly to keploy/tests/.
3. Run tests
keploy test-gen run --base-url http://localhost:8080 --output json
The JSON output includes pass/fail status, assertion failures, and extracted variables. The agent reads this to fix failing tests.
4. Coverage feedback loop (optional)
If you have an OpenAPI spec, add --spec for coverage analysis:
keploy test-gen run --base-url http://localhost:8080 --spec openapi.yaml --output json
The output includes a coverage section with next_steps—prioritized suggestions for uncovered endpoints. The agent reads these and generates targeted tests automatically.
Even without a spec, the Keploy platform builds schema coverage over time from your test runs. You can view this on the Keploy dashboard.
5. Sync results to platform
keploy test-gen run \
--base-url http://localhost:8080 \
--sync --app-id your-app-id --api-key $KEPLOY_API_KEY \
--output json
Results appear on your Keploy dashboard for team-wide visibility, reports, and alerts.
CLI Reference
keploy test-gen run
Execute test suites against a running API server.
| Flag | Description | Default |
|---|---|---|
--base-url | API server URL (required) | — |
--test-dir | Directory with test YAML files | ./keploy/tests |
--output | Output format: text, json, junit | text |
--spec | OpenAPI spec for coverage analysis (optional) | — |
--suite | Run specific suites by name | all |
--ci | Exit 1 on failure or low coverage | false |
--min-coverage | Coverage target (with --ci and --spec) | 80 |
--flaky-runs | Re-run failed suites N times | 0 |
--sync | Push results to Keploy platform | false |
--app-id | Keploy app ID (with --sync) | — |
--api-key | Keploy API key | $KEPLOY_API_KEY |
--auth-header | Auth header as "Key: Value" (quote in shell) | — |
--rate-limit | Max requests per second | unlimited |
--timeout | Per-request timeout (seconds) | 30 |
keploy test-gen coverage
Standalone coverage analysis without executing tests. Requires an OpenAPI spec.
| Flag | Description | Default |
|---|---|---|
--spec | OpenAPI spec file (required) | — |
--test-dir | Directory with test YAML files | ./keploy/tests |
--output | Output format: text, json | text |
--min-coverage | Coverage target percentage | 80 |
keploy test-gen init
Scaffold a test directory with examples.
| Flag | Description | Default |
|---|---|---|
--dir | Directory to initialize | ./keploy |
Test Suite YAML Format
Each file in keploy/tests/ contains one or more test suites separated by ---:
---
name: User_CRUD_Flow
description: Create, read, and delete a user
steps:
- name: Create user
method: POST
url: /api/users
headers:
Content-Type: application/json
body: '{"name":"Alice","email":"alice@test.com"}'
extract:
user_id: $.id
assert:
- type: status_code
expected_string: "201"
- type: json_equal
key: $.name
expected_string: '"Alice"'
- name: Get user
method: GET
url: /api/users/{{user_id}}
assert:
- type: status_code
expected_string: "200"
- name: Delete user
method: DELETE
url: /api/users/{{user_id}}
assert:
- type: status_code
expected_string: "204"
Assertion Types
| Type | Description | Example |
|---|---|---|
status_code | Exact HTTP status match | expected_string: "200" |
status_code_class | Status class match | expected_string: "2xx" |
status_code_in | Status in list | expected_string: "200,201,204" |
json_equal | Exact match at a JSON path | key: $.id, expected_string: '"abc"' |
json_contains | Subset match at a JSON path | key: $.data, expected_string: '{"name":"John"}' |
json_path | Alias for json_equal | key: $.id, expected_string: '"abc"' |
header_equal | Exact header match | key: Content-Type, expected_string: "application/json" |
header_contains | Header value contains a string | key: Content-Type, expected_string: "json" |
header_exists | Header key is present | key: X-Request-Id, expected_string: "true" |
header_matches | Header matches a regex pattern | key: Content-Type, expected_string: "application/.*json" |
schema | Validate response against a schema | expected_string: '{"type":"object","properties":{"id":{"type":"string"}}}' |
custom_functions | Custom JS function assertion | expected_string: 'function(req, res) { return res.status === 200; }' |
Variable Extraction
Use JSON paths to extract values from responses and use them in subsequent steps:
extract:
user_id: $.data.id
token: $.auth.access_token
Use in later steps: url: /users/{{user_id}}
Key rules:
- Variables are scoped to the test suite (not shared between suites)
- Must be extracted before use (by a previous step)
- Path syntax:
$.fieldorfield,$.nested.fieldornested.field(the$.prefix is optional) - Use dot notation for arrays:
$.users.0.id(correct) instead of$.users[0].id(brackets are not supported)
CI/CD Integration
GitHub Actions
- name: Run API tests
run: |
keploy test-gen run \
--base-url http://localhost:8080 \
--ci \
--output junit > test-results.xml
- name: Upload test results
uses: actions/upload-artifact@v4
with:
name: test-results
path: test-results.xml
Exit Codes
| Code | Meaning |
|---|---|
| 0 | All tests pass, coverage above threshold (if --spec provided) |
| 1 | Test failures, validation errors, coverage below threshold, or sync failure (in --ci mode) |
Coverage Feedback Loop
When --spec is provided, every run output includes a coverage section:
{
"coverage": {
"percentage": 72.5,
"target": 80,
"gap": "3 endpoints need tests to reach 80%",
"next_steps": [
{
"priority": "critical",
"action": "generate_test",
"endpoint": "DELETE /users/{id}",
"reason": "Zero test coverage.",
"hint": "Expected responses: 204 (Deleted), 404 (Not found)."
}
]
}
}
The agent reads next_steps and generates targeted tests for uncovered endpoints. This loop continues automatically until coverage targets are met.
Without an OpenAPI spec, you can still run tests and sync results. The Keploy platform builds schema coverage progressively from your test execution data over time.