pix_list_timing_threads

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior. The description adds meaningful context beyond that: busiest-first ordering, the distinction between PIX's packed thread_id and os_thread_id, and the meaning of stack_levels. It does not discuss pagination behavior, but the safety profile is already covered by annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is three dense sentences with no filler. The core purpose is front-loaded, and the second sentence packs essential ID semantics into a compact contrast between PIX's thread_id and the debugger's os_thread_id. Every clause earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With an output schema present, the description does not need to enumerate return fields. It covers ordering, ID semantics, and the dependency on pix_list_timing_processes, which is enough for correct invocation. The only real omission is explicit pagination or limit behavior, but that is minor given the schema exposes limit and cursor_position.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description carries the burden for parameter meaning. It explains process_id provenance and clarifies output-related identifiers such as thread_id, os_thread_id, and stack_levels, but it does not explain capture_id, limit, cursor_position, or timeout_seconds beyond their names. This is partial compensation with clear gaps.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description states clearly what the tool does: list every thread of one process with the data PIX recorded for each, ordered busiest first. It also distinguishes this tool from related siblings by tying process_id to pix_list_timing_processes and positioning it as the source of thread IDs for per-thread tools.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It explicitly says process_id comes from pix_list_timing_processes and that the returned thread_id is what per-thread tools consume. This tells an agent when to call this tool: after choosing a process, before invoking per-thread analyses. It effectively routes away from alternatives by naming the dependency and downstream consumers.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.