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

Annotations already declare read-only, idempotent, non-destructive. The description adds valuable context beyond annotations: return fields (accession, name, type, member databases), the type enum, and the fact that it is keyless. No contradictions.

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 concise sentences: purpose, context, and return format. No filler, front-loaded with the main verb and resource. The background on InterPro is brief and useful for context.

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 simple search tool with two well-documented parameters and no output schema, the description is quite complete. It lists the return fields and keyless requirement. It lacks explicit alternative routing, but that is covered by usage guidelines.

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 coverage is 100%, so baseline is 3. The description adds meaning by clarifying that the query searches over 'entry names/accessions', which is not explicitly in the schema description. This helps the agent understand the semantic scope of the query parameter.

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 verb+resource+scope: 'Search InterPro for protein families, domains, repeats and functional sites by keyword'. It distinguishes from siblings like get_entry (specific entry lookup) and entries_for_protein (protein-centric) by emphasizing keyword text search over entry names/accessions.

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?

It clearly implies when to use this tool: when searching by keyword rather than by accession or protein. It also notes 'Keyless' for accessibility. However, it does not explicitly name alternatives or exclusions, so it lacks explicit 'when-not-to-use' guidance.

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