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

Annotations already declare readOnlyHint=true and destructiveHint=false; the description adds non-obvious behavior beyond that: results carry 'evidence_grade T1 (single-extractor) until PRN-282 lands,' warning about evidence quality. It also discloses the cost distinction between claims and passages and notes that problem_slug/condition_slug are 'reserved for frame_tags[] pre-cache after PA-1153 ID-freeze.' No contradiction with 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?

Four informative sentences plus a bracketed capability/mirror note, with the core action front-loaded in the first sentence. The prose is efficient and purposeful, though internal identifiers like ASN-1577, PRN-282, and PA-1153 add jargon that is not essential for invoking the tool.

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 rich annotations, a 100%-covered schema, and an output schema present, the description is nearly complete: purpose, page context, evidence-grade caveat, cost, and API mirror are all covered. The main gap is that it doesn't explicitly differentiate this tool from sibling tools like vela.corpus.query or describe_topic, which matters for an agent with no other context.

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 the baseline is 3; the schema already documents all seven parameters. The tool description adds only general context ('given themes and/or emotions') and cost behavior, not meaningful new parameter-level meaning. It doesn't need to compensate, but it also doesn't substantially elevate parameter understanding.

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 opens with a specific action and resource: 'return passages and one-line claims from Vela's 762-work corpus' that illuminate themes/emotions. It also positions the tool as an 'inside-out layer' complement to the frame join's 'outside-in portrait,' helping distinguish it from neighboring corpus tools. The title alone would be useless, but the description supplies real semantic content.

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 intended use case is explicit: 'Designed for frame-family profile pages — PersonFrame × ProblemFrame × ConditionFrame — to add an inside-out layer.' It also provides cost-based guidance ('FREE for claims; costs one embedding for the passage path') that helps agents choose between claims and passage results. It does not explicitly name sibling alternatives or exclusion conditions, so it isn't a full routing contract.

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