Listener

Subscribe to network interception streams, manage active listeners, and unsubscribe.

otto listener subscribe-network

Subscribes to a network interception listener on a managed tab, streaming captured HTTP responses.

Usage

otto listener subscribe-network [options]

Flags

Flag	Shorthand	Required	Type	Default	Allowed values	Description
--tab-session		Yes	string			Tab session ID to attach the listener to
--site	-s	Yes	string			Site scope (e.g. reddit.com) — validated against tab URL
--pattern		No	string[]			URL glob patterns to capture (repeatable)
--request-host		No	string[]			Explicit cross-host allowlist (repeatable)
--mode		No	string	network	network, fetch, hybrid	Interception capture mode
--include-body		No	boolean	true		Include response body in updates
--include-headers		No	boolean	false		Include response headers (sensitive headers redacted)
--max-body-bytes		No	number	256000		Maximum response body bytes to capture
--mime-types		No	string[]			MIME prefix allowlist (repeatable)
--node-id		No	string	Auto-selected		Target node ID
--json		No	boolean	false		Output stream updates as NDJSON

Examples

# Basic network subscription for Reddit API traffic
otto listener subscribe-network \
  --tab-session <tabSessionId> \
  --site reddit.com \
  --pattern 'https://www.reddit.com/api/*'

# High-volume capture with body limit
otto listener subscribe-network \
  --tab-session <tabSessionId> \
  --site reddit.com \
  --request-host matrix.redditspace.com \
  --pattern 'https://matrix.redditspace.com/_matrix/client/v3/*' \
  --mode network \
  --max-body-bytes 200000

# Hybrid capture with headers and JSON output
otto listener subscribe-network \
  --tab-session <tabSessionId> \
  --site reddit.com \
  --mode hybrid \
  --include-headers \
  --json

Stream output

Each captured response is emitted as a listener_update frame. The stream continues until:

• otto listener unsubscribe is called with the subscribe requestId
• The tab session closes
• Ctrl+C is pressed (sends unsubscribe automatically)

The subscribe requestId is printed on start — save it to unsubscribe later from another terminal.

Exit codes

Code	Meaning
0	Subscribed and streaming
1	Subscription failed (invalid tab session, site mismatch, etc.)

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otto listener unsubscribe

Unsubscribes an active network listener by its subscribe requestId.

Usage

otto listener unsubscribe [options]

Flags

Flag	Shorthand	Required	Type	Default	Description
--target-request-id		Yes	string		The requestId returned by subscribe-network
--node-id		No	string	Auto-selected	Target node ID

Examples

otto listener unsubscribe --target-request-id <subscribeRequestId>

Exit codes

Code	Meaning
0	Unsubscribed successfully
1	Listener not found or relay error

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otto listener list

Lists active network listeners on the connected node.

Usage

otto listener list [options]

Flags

Flag	Shorthand	Required	Type	Default	Description
--node-id		No	string	Auto-selected	Target node ID
--json		No	boolean	false	Output as JSON

Examples

otto listener list

otto listener list --json

Exit codes

Code	Meaning
0	Listeners listed
1	Relay or node error

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Related commands

• otto test — run stream-capable commands with built-in listener management.
• Listener Development — build stream-capable commands.
• Logging and Debugging — diagnose listener and stream issues.