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'