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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety bar is low; the description still adds real value by disclosing that no artifact bytes are returned, that test-topic records are hidden from broad discovery, and that stored content is neither executed nor scientifically validated. This is substantive behavioral context beyond the 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?

Three tight sentences, front-loaded with the core purpose and ordering, then filtering rules, then return-content caveats. Nearly every clause carries information, though the final clause about contributor attribution and media type is slightly list-like and could be trimmed.

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 no output schema, the description usefully covers what comes back (metadata only, no bytes, attribution and media type) and how results are scoped and ordered. Pagination limits and the test-topic exclusion are covered, so an agent has enough to call it correctly; only the interplay with search_contributions remains 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 only 25% (only include_test is documented), so the description must compensate. It does: orbit_id is framed as a topic filter, page/per_page as pagination constrained by 'configured storage limits', and include_test's classification semantics are spelled out. It stops short of naming parameter names directly, but the meaning is recoverable.

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 and resource ('List public stored-artifact metadata'), plus ordering ('newest-first') and scope ('optionally within a topic'). The line 'No bytes are included' implicitly separates it from the sibling read_artifact, so an agent can tell the listing tool from the reading tool without opening a 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?

The description explains conditional behavior for filters: broad discovery excludes classified test topics unless include_test=true, while an explicit orbit_id includes its records regardless. However, it never names an alternative tool (e.g., search_contributions, read_artifact) or states when to prefer this listing over them, leaving routing guidance to inference.

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