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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds meaningful behavioral detail: tokenizing and expanding synonyms, ranking metadata plus observed tool descriptions, and supporting operational-grade/auth/latency/category filters. No contradiction.

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?

Two sentences; first sentence is front-loaded with purpose and example, second sentence gives alternative usage. No wasted words; all content contributes to understanding.

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?

The tool has an output schema and thorough annotations, plus a description covering behavior, filters, ranking logic, and alternative tools. This is complete for an agent to select and invoke correctly.

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 has 100% coverage of all 6 parameters with clear descriptions and enums. The description mentions filter types (auth/latency/category) and query expansion context, but it does not add substantial meaning beyond what the schema already documents.

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?

Specifically states 'Search the MCP evidence registry' with a natural multi-word task, clearly identifying the verb and resource. Differentiates from siblings like search_tools and search_trust_evidence by the registry scope and task-based approach.

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?

Provides explicit direction: 'Use get_trust_receipt or search_trust_evidence for security, data, citation, claim, and response evidence.' This tells the agent when to choose alternatives, complementing the search use case.

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