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

With no annotations, the description carries the full burden and does disclose the critical behavior: on hosted there is no cross-request memory, so the call degrades to an honest_note rather than real traces, and stdio supports ROBOPARTS_TRACE_FILE JSONL persistence. It stops short of describing the exact return payload shape.

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?

Three tightly-packed sentences with the purpose front-loaded and the hosted/stdio caveat immediately after; no filler despite mixed Chinese/English.

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?

For a tool that is effectively a no-op on hosted, the description explains the degradation and the stdio alternative, which is the key thing an agent needs. The only gap is that the actual payload returned by stdio mode is not described, and there is no output schema.

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 100%, so tool/limit/since/redact are already documented in the schema. The description only echoes the redact default, adding no syntax or format detail beyond the schema; baseline 3 is appropriate.

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?

States a specific verb+resource: export call traces, redacted by default. It is distinguishable from trace_replay by the export/persist framing, though it never names trace_replay as the contrast.

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?

Gives a concrete when-it-works / when-it-doesn't split: the ring buffer exists only in the stdio npm package, so on the hosted endpoint the tool returns an honest_note instead of data. It does not explicitly route the agent to trace_replay for replay, leaving that inference to the agent.

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