reverse-engineering-anything/docs/playwright-traces.md

Offline Playwright traces

Use inspect_playwright_trace or inspect-playwright-trace with an existing local Playwright trace v10 ZIP. Import is offline: recorded URLs are not requested, and no browser, application or trace viewer is started.

rea inspect-playwright-trace /absolute/trace.zip --json
rea inspect-playwright-trace /absolute/trace.zip --detail summary \
  --evidence_output /absolute/new-evidence.bundle.json --json

MCP defaults to a compact summary and retains complete supported Evidence. CLI defaults to complete delivery; summary and selected pages require an absent --evidence_output destination, so later queries can read the original parent.

{
  "name": "inspect_playwright_trace",
  "arguments": {
    "path": "/captures/trace.zip",
    "view": {
      "kind": "playwright-trace",
      "collection": "events",
      "kinds": ["network"],
      "fields": ["method", "url", "status"],
      "limit": 10
    }
  }
}

view takes precedence over detail. The retained parent can be queried with inspect_analysis_view; CLI can use the same request against an exported Evidence bundle with inspect-analysis-view.

Facts, selection and text

The playwright-trace view offers:

Collection	Available selection
events	Batch event/stream/call IDs, event kinds, fields, row offset and limit
streams	Batch stream IDs, fields and row pages
members	Batch member IDs, exact archive paths, fields and row pages
diagnostics	Codes, fields and row pages
event-text	One event ID, UTF-16 character offset and limit

An omitted filter selects all retained rows; an explicit empty filter selects none. Minimal event rows keep event/stream IDs, source member/line, producer ordinal, kind and credential-redaction status. Page exhaustion describes only the selected facts and never establishes complete recording coverage.

Default event pages return at most 256 UTF-16 code units in text_preview, with explicit text coverage. Continue from that preview's next_offset using collection: "event-text", its event_id, offset, and a character limit (default 2,048). Character offsets do not split surrogate pairs. Explicit fields: ["text"] returns the complete interpreted text value; reported returns the retained supported payload and sidecars remain selectable. Complete Evidence remains accessible through ordinary bundle operations.

Source and coverage

Archive SHA-256 and directory occurrence bind stable member identity. Each event retains its member ID, physical one-based NDJSON line and zero-based physical line ordinal. Headline times retain producer monotonic milliseconds, without aligning stream clocks. Counts derive from the retained supported records. Call IDs are producer values; they do not establish unique actions across streams or imply a successfully completed before/after pair. There is no inferred total ordering or clock alignment between .trace and .network.

Member path preserves the reader's original ZIP name; logical_path separately records its normalized interpretation. Resource references, exact paths filters and trace/network profile pairing use original names, so resources/x and ./resources/x remain distinct. Reader limitations remain attached to each member and keep source interpretation partial when present.

decoder_profile names the selected interpretation policy, not a verified source version. Trace members require an initial numeric v10 context header. Other declared versions are refused. Missing, malformed, repeated or ambiguous profiles remain unknown; network members require one unambiguous paired trace profile. Valid siblings of malformed records stay useful, with explicit diagnostics. Unsafe numeric values are not rounded: exact literals stay in sidecars.

Interpreted facts cover action boundaries (class/method, title, call/page IDs, selected navigation URL/selector, recorded times and available error text), console text/location, network metadata and screencast references. Other action arguments, results, context options, DOM, stacks, unsupported event types and resource contents are outside this version's interpretation. These omissions are scope limitations, not assertions that omitted values are secrets or absent. Original archive bytes remain the complete raw source.

Known HAR transport credentials and structured network, navigation and console-location URL userinfo are excluded using the existing capture projection. Ordinary names, query values, console text and caller data are preserved. Network numeric/redaction pointers are relative to reported; combine them with the event source's record_pointer (/snapshot) to locate the original NDJSON value. Resource-reference pointers already address the physical record.

Resource references distinguish present-unread, missing, ambiguous and unavailable. Presence means directory metadata only: screenshots and bodies are not read or validated. Member declared_bytes and declared_compressed_bytes come from the ZIP directory; they are not measurements of unread payloads. Only decoded stream members have verified ZIP CRC and size. Duplicate names keep separate occurrence IDs; no filename silently picks a resource. Recording completeness always remains unknown, including after all retained pages have been read.

Bounds and verification

Each decoder admits one archive import at a time; concurrent imports receive a retryable capacity error. Retained queries do not require another import. Resource policies admit a 256-MiB archive, 32 MiB of decoded streams, a conservative 32-MiB retained-facts representation, 4-MiB metadata reads and 4-MiB physical lines. JSON parsing additionally checks heap headroom, a 131,072-node record allowance and the shared 64-level capture nesting budget. These are resource policies, not Playwright format limits. Paging or field selection does not increase parsing allowances; choose a smaller complete recorder chunk when admission fails.

The owned fixtures in tests/fixtures/playwright-trace/ preserve actual Playwright 1.64.1 v10 recorder text. Public CLI/MCP tests exercise advertised schemas, retained and bundle queries without the source file, partial facts, credential exclusion, bounded Unicode previews, and a loopback listener that must receive no import-time requests. Recorder/version/platform compatibility outside this verified profile is unverified.