meticulous simulate
meticulous simulate --sessionId=<id> [options]
# alias:
meticulous replay --sessionId=<id> [options]
Purpose: Replay a recorded session in a Chromium browser. Stubs network requests using recorded responses, then optionally takes screenshots and diffs them against a base replay. The primary command for local debugging and manual replay testing.
Replay Target
Exactly one of these determines what URL the session is replayed against:
| Option | Description |
|---|
| *(none)* | Replay against the original URL the session was recorded on |
--appUrl=<url> | Replay against a specific URL (e.g., http://localhost:3000) |
--appUrl=uploaded-assets://<deploymentUploadId> | Replay against previously uploaded static assets |
--appUrl=uploaded-container://<containerUploadId> | Replay against a previously uploaded Docker container |
--simulationIdForAssets=<id> | Replay against assets snapshotted from a prior simulation (mutually exclusive with --appUrl) |
Core Options
| Option | Type | Required | Default | Description |
|---|
--sessionId | string | yes | — | ID of the session to replay |
--apiToken | string | no | — | Meticulous API token; prompts OAuth login if omitted in interactive context |
--commitSha | string | no | — | Git commit SHA to associate with this replay |
--appUrl | string | no | — | URL to replay against (see Replay Target above) |
--simulationIdForAssets | string | no | — | Use snapshotted assets from this prior simulation (conflicts with --appUrl) |
Screenshot Options
| Option | Type | Default | Description |
|---|
--takeSnapshots / --screenshot | boolean | true | Take a visual snapshot at the end of the replay |
--storyboard | boolean | false | Also take screenshots throughout the replay (requires --takeSnapshots) |
--baseReplayId / --baseSimulationId | string | — | Replay ID to diff screenshots against; if omitted, screenshots are stored but not compared |
--diffThreshold | number | 0 | Max proportion of changed pixels (0–1) before a diff is flagged |
--diffPixelThreshold | number | 0.1 | Per-pixel color difference tolerance (0–1) |
Step-Through Debugger
meticulous simulate --sessionId=<id> --appUrl=<url> --debugger
meticulous simulate --sessionId=<id> --appUrl=<url> --debugger --startAtEvent=95
| Option | Type | Default | Description |
|---|
--debugger | boolean | false | Open an interactive step-through debugger that advances the replay event by event |
--startAtEvent | number | — | Auto-advance to this event index when the debugger opens (requires --debugger). E.g., --startAtEvent=95 jumps to "Event #95". |
Constraints:
--debugger cannot be combined with --headless--startAtEvent requires --debugger--storyboard requires --takeSnapshots
Browser Execution Options
| Option | Type | Default | Description |
|---|
--headless | boolean | false | Run browser in headless mode |
--devTools | boolean | false | Open Chrome DevTools |
--bypassCSP | boolean | false | Bypass Content Security Policy |
--shiftTime | boolean | — | Shift the browser clock to the recording time |
--networkStubbing | boolean | true | Stub network requests with recorded responses |
--skipPauses | boolean | false | Fast-forward through delays in the recording |
--moveBeforeMouseEvent | boolean | — | Simulate mouse movement before each click/hover event |
--disableRemoteFonts | boolean | false | Block remote font loads |
--noSandbox | boolean | false | Pass --no-sandbox to Chromium |
--maxDurationMs | number | none | Abort replay after N milliseconds |
--maxEventCount | number | none | Abort replay after N events |
--essentialFeaturesOnly | boolean | false | Disable non-essential features (e.g., video recording) to reduce noise when debugging |
--enableCssCoverage | boolean | false | Collect CSS coverage during the replay |
--cookiesFile | string | — | Path to a cookies JSON file to inject before replay starts |
--sessionIdForApplicationStorage | string | — | Seed application state (cookies, localStorage, sessionStorage) from this session's recorded state |
Network Debugging Options
These options enable verbose logging of network activity during replay, useful for diagnosing request-matching or stubbing issues:
| Option | Type | Description |
|---|
--networkDebuggingRequestRegexes | string[] | Log requests whose URLs match any of these regexes |
--networkDebuggingTransformationFns | string[] | Log specific request transformations (logs all if omitted) |
--networkDebuggingRequestTypes | string[] | Filter by request type: original-recorded-request, request-to-match |
--networkDebuggingWebsocketUrlRegexes | string[] | Log WebSocket connections whose URLs match any of these regexes |
Examples
# Basic replay against local dev server
meticulous simulate --sessionId=abc123 --appUrl=http://localhost:3000
# Replay with screenshot diff against a known-good base
meticulous simulate \
--sessionId=abc123 \
--appUrl=http://localhost:3000 \
--baseReplayId=rpl_good \
--takeSnapshots
# Step through event-by-event starting at event 42
meticulous simulate \
--sessionId=abc123 \
--appUrl=http://localhost:3000 \
--debugger \
--startAtEvent=42
# Debug network stubbing for requests to /api/users
meticulous simulate \
--sessionId=abc123 \
--appUrl=http://localhost:3000 \
--networkDebuggingRequestRegexes='/api/users'
