[Bug] (with repro) TaskOutput tool incorrectly hidden from subagents

Bug Description
The TaskOutput tool appears to be incorrectly hidden from subagents.

Here's a kinda minimal repro, after I asked claude to "Launch a subagent to do something slow and long running, in the background. Then launch a subagent to try to consume the output of the background subagent by using TaskOutput.":

  ---
  Let me launch a background subagent that does something slow, then launch a second subagent to consume its output:

⏺ Task(Slow background task)
  ⎿  Backgrounded agent                                                                                                                                                                                                              
  ⎿  Prompt:
       Do something that takes a little while - search for all Swift files in this repository and count how many contain "@Observable", then count how many contain "ObservableObject". Report both counts and which pattern is more
       prevalent. Take your time and be thorough.

∴ Thinking…

  Good, the first subagent is now running in the background. Now I need to launch a second subagent that will use TaskOutput to consume the output of the first subagent. I'll pass the agent ID to the second subagent so it can use 
  TaskOutput to get the results.

⏺ Background agent launched (ID: a29602e). Now launching a second subagent to consume its output:                                                                                                 06:19 PM  claude-opus-4-5-20251101

⏺ Task(Consume background task output)
  ⎿  Prompt:
       There is a background subagent running with ID "a29602e" that is counting @Observable vs ObservableObject usage in Swift files.

       Your task is to:
       1. Use the TaskOutput tool to wait for and retrieve the results from that background agent (use task_id: "a29602e", block: true)
       2. Once you have the results, analyze them and provide a brief summary
       3. Add your own observation about what this pattern prevalence might indicate about the codebase's modernity

       This tests the subagent-to-subagent communication pattern via TaskOutput.

     > There is a background subagent running with ID "a29602e" that is counting @Observable vs ObservableObject usage in Swift files. 
     Waiting…ude task-output a29602e --block)
     Error: Exit code 1
     Waiting…ude task-output a29602e)
     It looks like you're asking me to retrieve output from a task, but I don't have a specific task ID to check. This appears to be the start of a new session.
     Waiting…ude tasks)
     I'll analyze the user's request and evaluate the relevant skills and agents.
  ⎿  Interrupted · What should Claude do instead?

⏺ Agent "Slow background task" completed.
  ⎿  Interrupted · What should Claude do instead?

Environment Info

• Platform: darwin
• Terminal: Apple_Terminal
• Version: 2.0.75
• Feedback ID: cf6e2445-e2ac-4821-8a46-2a974897951b

Errors

[{"error":"Error: Request was aborted.\n    at OT.makeRequest (file:///Users/alexanderriccio/.nvm/versions/node/v24.10.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:857:3940)\n    at process.processTicksAndRejections (node:internal/process/task_queues:105:5)","timestamp":"2025-12-22T23:21:42.916Z"},{"error":"Error: Request was aborted.\n    at d71 (file:///Users/alexanderriccio/.nvm/versions/node/v24.10.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:1346:19457)\n    at d71.next (<anonymous>)\n    at PW9 (file:///Users/alexanderriccio/.nvm/versions/node/v24.10.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:4593:1426)\n    at process.processTicksAndRejections (node:internal/process/task_queues:105:5)\n    at async file:///Users/alexanderriccio/.nvm/versions/node/v24.10.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:4591:3799\n    at async d00 (file:///Users/alexanderriccio/.nvm/versions/node/v24.10.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:1007:2037)\n    at async zHA (file:///Users/alexanderriccio/.nvm/versions/node/v24.10.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:4591:3769)\n    at async ew (file:///Users/alexanderriccio/.nvm/versions/node/v24.10.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:2207:3569)\n    at async file:///Users/alexanderriccio/.nvm/versions/node/v24.10.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:2709:1990\n    at async file:///Users/alexanderriccio/.nvm/versions/node/v24.10.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:2709:2831","timestamp":"2025-12-22T23:21:43.313Z"}]