Logging

The server logs everything that happens between the agent, the MCP server and the browser. Each entry is one JSON object per line (pino format), so you can read it with jq or send it to any log pipeline.

Where logs go

Destination	Default level	Setting
stdout (`docker compose logs -f`)	`info`	`LOG_LEVEL`, `LOG_FORMAT=json\|pretty`
Rotating file, `./logs/` on the host (`/app/logs` in the container)	`debug`	`LOG_FILE_LEVEL`, `LOG_FILE_MAX_SIZE`, `LOG_FILE_MAX_FILES`
Dashboard "Logs" panel (last 2,000 entries)	`debug`	—

Files rotate daily and when they reach LOG_FILE_MAX_SIZE (default 20 MB). The newest LOG_FILE_MAX_FILES files are kept, and logs/current.log always points at the file being written.

What is logged

Every entry has time, level/levelName, component and msg. Components:

`component`	Level	What
`main`	info	Startup configuration summary (no secrets), ready URLs, shutdown
`http`	info/warn	Every HTTP request: method, path, status, duration, MCP session id, client address, user agent
`mcp-session`	info	MCP session start (client name/version, protocol version) and end (reason, number of tool calls, duration)
`mcp`	debug	Every JSON-RPC message in (`dir: "in"`) and out (`dir: "out"`) per session, with payloads summarized
`tool`	info/warn	Every tool call: arguments, calling client, queue depth. Then its result, duration and error flag. Same `callId` on both lines. Calls rejected before running (invalid arguments, unknown tool) are logged as warnings too
`browser`	info	Tabs opened, closed and switched, page navigations, connection loss and recovery
`cdp`	debug	Every CDP command sent (method, params), every response (duration, result or error) and every CDP event
`page-console`	debug/info/warn	Page `console.*` output and uncaught exceptions, with page URL
`page-network`	debug	Every finished request: method, URL, status, type, size, duration
`obscura`	info/warn/error	Obscura process lifecycle: version, arguments, readiness, crashes, restarts
`obscura-engine`	per line	Obscura's own log output, parsed into levels (`target` = Rust module)
`live-view`	info/debug	Viewers connecting and leaving, screencast start and stop
`dashboard`	debug	Dashboard event streams opened and closed
`agent`	info/warn	Sub-agent runs: created (input), started (browser), finished (status, steps, duration, token usage, compactions, outcome, sources, script tests)
`agent-llm`	debug/info	Every model request (messages, tools, prompt size) and response (duration, finish reason, token usage, tool calls, answer text), retries
`script`	info	Script runs (parameters, result, duration, browser calls) and each `log()` line of the script

Everything a sub-agent or script does carries agentRunId (sub-agent run), browserId (its private browser, e.g. agent-r1a2b3c4) or script/scriptRunId. Tool calls made by sub-agents appear under component: "tool" like any other call, with the client label agent:<kind> <run id>.

Sub-agent transcripts

With AGENT_TRANSCRIPTS=true (the default), every run also writes logs/agent-runs/<time>_<kind>_<run id>.json. It contains the input, the outcome, the saved notes, cited sources, visited pages, script tests, every step (model timing, token usage, full reasoning, tool calls and result previews) and the complete message transcript. The newest 300 transcripts are kept.

Payload summarization

Logs stay readable and bounded without dropping information silently:

Strings longer than LOG_MAX_STRING_LENGTH (2,000 characters) are cut, and the entry records how many characters were removed: …(+1234 chars).
Base64 images and PDFs are replaced by <binary 51234 bytes sha256:…>.
Authorization and Cookie headers are always redacted.
With LOG_REDACT_SECRETS=true (the default), secrets are masked in logs and on the dashboard. The agent still receives the real values; only logs are masked. Set it to false for full-fidelity debugging logs. Masked:
- values typed into password- or OTP-like fields (type=password, or a name, label, autocomplete attribute or selector mentioning password, token, OTP, PIN, CVV or card number). A call that targets a field by an arbitrary CSS selector is logged with [REDACTED] first; the result line then shows the real value if the field was not sensitive.
- cookie values in browser_set_cookie arguments, browser_get_cookies and browser_storage_state results, browser_set_storage_state input, and CDP cookie commands.
- Cookie, Set-Cookie, Authorization, Proxy-Authorization and X-API-Key headers in CDP network events.
LOG_CDP_EVENTS=false stops logging CDP events (network and lifecycle noise) and keeps commands and responses.

Useful queries

bash

# Follow tool calls live
tail -F logs/current.log | jq -c 'select(.component=="tool") | {time, msg, args, durationMs, isError}'

# Everything one MCP session did
jq -c 'select(.sessionId=="<session-id>")' logs/current.log

# Failed tool calls with their error text
jq -r 'select(.component=="tool" and .isError==true) | "\(.time) \(.tool): \(.result.content[0].text)"' logs/current.log

# The 10 slowest browser (CDP) commands
jq -s '[.[] | select(.component=="cdp" and .durationMs!=null) | {method, durationMs}] | sort_by(.durationMs) | reverse | .[:10]' logs/current.log

# Page JavaScript errors
jq -r 'select(.component=="page-console" and (.pageLevel=="error" or .pageLevel=="exception")) | "\(.pageUrl): \(.msg)"' logs/current.log

# One sub-agent run, start to finish (tool calls and model turns)
jq -c 'select(.agentRunId=="<run id>" or .runId=="<run id>") | {time, component, msg, tool, durationMs}' logs/current.log

# Model latency and token usage per sub-agent step
jq -c 'select(.component=="agent-llm" and .usage) | {runId, step, durationMs, usage, finishReason}' logs/current.log

# Pretty-print the live stream
tail -F logs/current.log | npx pino-pretty

Example

A single browser_navigate call produces, in order:

json

{"level":30,"component":"http","method":"POST","path":"/mcp","status":200,"durationMs":663,"sessionId":"65438e50-…","msg":"POST /mcp 200"}
{"level":20,"component":"mcp","dir":"in","method":"tools/call","message":{"params":{"name":"browser_navigate","arguments":{"url":"https://quotes.toscrape.com/js/"}}},"msg":"MCP ← tools/call"}
{"level":30,"component":"tool","tool":"browser_navigate","callId":"0b7718f0","args":{"url":"https://quotes.toscrape.com/js/"},"client":"lmstudio-mcp-server-session 1.0.0","queued":0,"msg":"tool call browser_navigate"}
{"level":20,"component":"cdp","dir":"out","method":"Page.navigate","params":{"url":"https://quotes.toscrape.com/js/","waitUntil":"load"},"msg":"CDP → Page.navigate"}
{"level":20,"component":"cdp","dir":"in","method":"Page.navigate","durationMs":612,"msg":"CDP ← Page.navigate (612 ms)"}
{"level":20,"component":"page-network","method":"GET","url":"https://quotes.toscrape.com/static/main.css","status":200,"type":"Stylesheet","size":1124,"durationMs":88,"msg":"GET https://quotes.toscrape.com/static/main.css → 200"}
{"level":30,"component":"browser","tabId":"tab-1","url":"https://quotes.toscrape.com/js/","msg":"page navigated"}
{"level":30,"component":"tool","tool":"browser_navigate","callId":"0b7718f0","durationMs":657,"isError":false,"result":{"content":[{"type":"text","text":"Navigated to https://quotes.toscrape.com/js/ — \"Quotes to Scrape\" (HTTP 200)"}]},"msg":"tool result browser_navigate (657 ms)"}
{"level":20,"component":"mcp","dir":"out","rpcId":3,"message":{"result":{"content":[…]}},"msg":"MCP → result"}