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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the read-only safety profile is covered. The description adds valuable extra context: 'missing claim indexes are returned as unresolved, not fabricated,' which is a transparency guarantee beyond the annotations. This justifies a score above baseline.

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 description is two sentences, front-loading the tool's purpose and safety, then efficiently covering parameters and a key behavioral note. No wasted words, though the second sentence is somewhat dense with multiple clauses. Overall, concise and structured.

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 with 14 optional parameters and an output schema, the description adequately covers purpose, parameter selection, and a caveat about missing claim indexes. It does not explain what happens when no parameters are provided, but the schema allows that and the output schema handles return values, so the description is reasonably complete.

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 each parameter is already well-documented. The description names several key parameters and hints at their grouping ('pass query, claim_text, claim_hash, river_tripcode, or issuer') but does not add semantic 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?

The description clearly states the tool's purpose: 'search one River or claim index for matching thesis claims.' This provides a specific verb and resource. While it doesn't explicitly name sibling tools, the phrase 'one River or claim index' and the tool name 'by_claim' help differentiate it from issuer-based searches, though the distinction is not fully explicit.

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 implies usage by listing relevant parameters ('pass query, claim_text, claim_hash, river_tripcode, or issuer'), but it does not explicitly state when to prefer this tool over alternatives such as deltasignal_search_by_issuer. No when-not-to-use guidance is provided, so usage context is implied rather than explicit.

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