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

Annotations already declare readOnlyHint=true and destructiveHint=false; the description goes further by adding 'newest first' ordering, owner-scoping, the durable nature of traces, and the Authorization: Bearer requirement. No contradiction with the read-only 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 core action and ordering are front-loaded, followed by motivation, filter semantics, scope, and auth. Each sentence carries distinct information; the slight length is justified by the number of filters and operational caveats it covers.

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 5-param read-only list tool with no output schema, this covers everything an agent needs to invoke it correctly: purpose, relation to rig_run, all relevant filters, ordering, owner scope, and auth. No critical operational detail appears missing.

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 coverage is 100%, so the baseline is 3; the description adds real value by clarifying parent_trace_id as step-traces under a run, trace_kind as 'run' vs 'atomic', and giving status examples. It doesn't add much beyond the schema for `limit`, but the schema already provides that.

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?

Opens with 'List your Traces — the durable record of what a run DID, newest first', a precise verb+resource that immediately separates it from rig_run (the start report) and from trace_get (implied by listing semantics). The purpose is unambiguous even before consulting the schema.

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?

Explicitly frames this as 'the other half of rig_run' and states the pain point it solves: without it an agent can run a rig and never learn whether it worked. It also gives exact filter use cases, especially parent_trace_id for seeing which steps ran and which were skipped.

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