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

Annotations already mark the tool as read-only, idempotent, and non-destructive. The description adds behavioral nuance beyond those annotations: the revision count 'stays 0 on free', and an ambiguous partial title match 'is refused with the candidates'. These are useful, non-obvious behaviors that help an agent predict outcomes. No contradiction with annotations exists.

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, no filler. The core action and lookup keys are front-loaded, and the second sentence covers the important edge case without over-explaining. Every clause earns its place.

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 read tool with two optional parameters, the description covers the return contents and the main edge case. The absence of an output schema is mitigated by listing the returned fields. The only minor gap is that neither parameter is formally required by the schema, so an agent might wonder what happens if both are omitted, but 'by id or title' strongly implies one is needed.

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 the schema already documents id and title individually. The description adds value by clarifying the relationship between the two parameters: they are alternative lookup keys ('by id or title'), and one can be partial while the other is exact. It also explains the consequence of an ambiguous title match, which the schema does not convey.

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 opens with a specific verb and resource: 'Return one clause in full by id or title.' It also enumerates what 'full' includes (body, category, tags, jurisdiction, variables, revision count), and the word 'one' distinguishes it from listing/searching tools. This is unambiguous and clearly separates clause_get from clause_list and clause_search.

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 description makes the selection context clear: use this tool when you need a single complete clause and have an id or title. The partial-title refusal behavior also tells the agent how the tool behaves in ambiguous cases. It does not explicitly name alternatives like clause_list or clause_search, but the 'one clause in full' framing makes the intended usage evident.

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