MCP cdp_debugger_eval_frame

Description

Evaluates a JS expression scoped to a specific paused call frame via CDP Debugger.evaluateOnCallFrame -- sees that frame's locals and closures, not just globals. Get callFrameId from cdp_debugger_state's callFrames[].callFrameId while paused. Use this instead of cdp_eval specifically when you need access to a paused frame's own locals/closures, not because cdp_eval stops working -- it doesn't.

Delegates internally to debug_eval (after resolving callFrameId to a frameIndex via the native cdp_debugger_state route) -- the response uses debug_eval's shape (result.value/result.type, plus the richer result.variables for a container), not a raw CDP evaluateOnCallFrame RemoteObject.

Required parameters:

• callFrameId (string): From cdp_debugger_state's callFrames[].callFrameId.
• expression (string): JS expression to evaluate in that frame's scope.

Optional parameters:

• sessionId (string): Session id returned by cdp_session_create. Uses the active session when omitted.

Aliases

Alias of debug_eval; runtime="typescript"; Resolves callFrameId against the paused state to frameIndex; rejects missing or stale frame IDs.

See also

• Alias of MCP debug_eval
• HTTP cdpGetDebuggerState (GET /api/cdp/debugger/state)
• HTTP debugEval (POST /api/debug/eval)
• rk cdp debugger eval-frame

Parameters

additionalProperties: false

callFrameId

From cdp_debugger_state's callFrames[].callFrameId.

expression

JS expression to evaluate in that frame's scope.

sessionId

Session id returned by cdp_session_create. Uses the active session when omitted.