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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the description earns credit for adding what they cannot: the return shape ('scored candidates with matched_in for transparency') and the ranking mechanism (field-weighted keyword search vs. optional embeddings cosine re-ranking). It still omits whether results are deterministic across runs or how ties/scores are scaled.

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, front-loaded with the core action and return value. The final two sentences on the base vs. embeddings backend are somewhat implementation-level detail, but they are compact and relevant to interpreting the ranking.

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 carries the burden of explaining returns and does so partially (scored candidates with matched_in), but leaves the score semantics, ordering guarantees, and the shape/identifiers needed for follow-up calls (e.g., get_dysfunction, resolve_id) unspecified. Adequate for invocation, incomplete for interpreting and chaining results.

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 67%: observations and modality_hint are documented in the schema, while limit is not. The description reinforces the observations parameter ('the observed behaviours') but says nothing about limit bounds or when to set modality_hint, so it adds little beyond the schema.

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 states a specific verb and resource: 'Rank candidate dysfunctions matching the observed behaviours', which is more precise than the sibling list_dysfunctions or get_dysfunction. It implies the tool is for matching-based ranking rather than retrieval by id, though it never names a sibling to draw the contrast explicitly.

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?

There is no explicit when-to-use or when-not-to-use guidance, and no reference to the closely named sibling get_differential_map, which an agent could easily confuse with this tool. Usage must be inferred entirely from the phrase 'matching the observed behaviours'.

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