replay_trace

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

The description adds meaningful behavioral context beyond the annotations: the operation runs in the background, is session-based, returns a session id, and produces profiling output in the session log. It does not contradict the annotations, and it explains the asynchronous nature better than the bare hint fields.

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 short and front-loaded, opening with the core purpose and return value. The second block about profile values is useful but formatted as a bare fragment; still, it contains no filler and 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?

The description covers the asynchronous session model, return value, profiling profiles, and status polling. It is incomplete, however, because it does not explain the 'trace' argument format, the meaning of 'api', 'headless', or 'extra_args', or what conditions cause the replay to finish or fail.

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 must carry parameter meaning. It documents the 'profile' parameter with its allowed values and its effect, but says nothing about 'api', 'trace', 'headless', or 'extra_args', leaving most parameters underspecified for an agent.

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 clearly states a specific verb and resource: 'Replay a trace in the background (session-based).' It also states the return value, a session id. It does not explicitly distinguish itself from sibling tools like trace_launch or sed_trace, but the replay action is distinct enough to understand the core purpose.

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 gives implicit workflow context by saying profiling output 'lands in the session log -- poll it with trace_status,' which tells the agent how to follow up. However, it does not explain when to choose this tool over alternatives, mention any exclusions, or describe prerequisites for replaying a trace.

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