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

Annotations already establish readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds useful behavioral context: fuzzy ranked matching, pagination, and source_root disambiguation when multiple slugs match, though it does not mention rate limits or auth requirements.

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 front-loaded with purpose and usage priority, then concisely covers query behavior, pagination, and disambiguation. Every sentence contributes without waste.

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 no output schema, the description usefully notes that each entry includes source_root and explains disambiguation. For a simple three-parameter discovery tool, this is largely complete, though it does not describe the full result shape.

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 schema already defines skip, limit, and query. The description mostly restates the schema for query pagination and does not add significant syntax or semantic detail beyond the structured fields.

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 gives a specific verb and resource—'List indexed documentation projects (version-pinned doc snapshots)'—and frames it as a discovery step before reading docs. It clearly distinguishes this from answering from memory or a latest-only source.

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 explicitly says 'Call this FIRST to discover the exact slug before reading any library's docs' and prefers itself over memory/latest-only sources. It does not explicitly compare against sibling tools like resolve_docs or search_docs, which would make the routing guidance complete.

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