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

Annotations already declare readOnlyHint=true, so the safe read nature is known. The description adds behavioral context by specifying that it returns 'matching metrics and their most citable segments,' which clarifies the output focus beyond a generic search. This extra detail 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-loaded with the core action, and includes practical examples. Every word earns its place, with no fluff or repetition.

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?

This is a simple one-parameter tool with no output schema. The description explains what the tool returns ('matching metrics and their most citable segments'), which is sufficient for an agent to understand the outcome. It does not mention edge cases or pagination, but those are not critical for a single-query search tool.

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 single parameter 'query' is described as 'Keywords to search for (at least 2 characters)'. The description adds example keywords ('dmarc', 'certificate expiry uk', 'subdomain takeover') but does not significantly enhance meaning beyond the schema, so 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 specifies a clear action ('Search'), a resource ('Quiet Failures base rates'), and a method ('by keyword') with examples. It distinguishes from sibling tools like get_base_rate (likely fetch by ID) and list_base_rates (list all) by emphasizing keyword-based search and returning matching metrics and segments.

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 the tool is for keyword search, but it does not explicitly state when to use it instead of siblings like get_base_rate or list_base_rates. There is no mention of exclusions or alternatives, so the usage context is only implied, not explicit.

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