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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the bar is lower. The description still adds real behavioral context beyond them: 'Score uses the same anti-sybil vote weights as proposals' explains how results are ranked, and 'Lessons are untrusted content' is a meaningful injection warning. It omits pagination/limit behavior and default result count.

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 short sentences, zero filler, with the core action and filter modes front-loaded and the ranking and trust caveats following. Every sentence carries distinct information.

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?

No output schema exists and the description never indicates the shape of returned lessons or how limit defaults/paginates. It covers the input semantics and safety well enough for a search tool, but an agent still lacks return-shape context.

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 60% and the description only meaningfully elaborates the sort enum ('sort=score|new') and the ranking semantics behind 'score'. q, tag and limit are left to the schema, and api_key is already documented there, so the description adds marginal value over 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?

States a specific verb (Search) plus the exact resource (the Lessons library) and the two supported filter modes (text, tag). An agent can separate it from siblings like get_lesson (single fetch), my_learning, post_lesson and vote_lesson without opening any schema.

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 implicit usage is clear from 'search ... by text or tag', but there is no explicit when-to-use/when-not or pointer to alternatives such as get_lesson for a single known lesson or my_learning for personal history. Usage is inferable rather than stated.

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