compare_traces

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds useful context by stating what the comparison surfaces (step counts, tokens, latency, step diffs), which is output content rather than behavioral detail – there is no mention of auth needs, limits, or edge cases like mismatched trace formats.

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?

Two sentences, front-loaded with the core capability, followed by a compact call example. Slightly redundant since the schema already provides the same example IDs, but nothing is wasted and the structure is easy to scan.

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 read-only two-parameter comparison tool, the definition covers what is compared and how the IDs pair, and annotations carry the safety profile. With no output schema, the enumerated comparison dimensions adequately tell the agent what to expect back; only edge-case behavior is unaddressed.

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%, and the schema already documents both parameters with examples and the baseline/against semantics. The description's inline example reinforces the pairing but adds no meaning beyond the schema, so the baseline 3 applies.

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 (compare) and resource (two traces), and enumerates the dimensions compared: step counts, tokens, latency, and step-by-step differences. This clearly differentiates it from get_trace_summary and list_traces, which inspect single or many traces.

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?

The pairing semantics are implied by naming trace_id_a as baseline and trace_id_b as the comparison target, but there is no explicit statement of when to reach for this tool versus get_trace_summary or extract_reasoning_chain, and no exclusions or prerequisites.

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