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

With no annotations, the description carries the full burden and does substantial work: it discloses the normalization basis ('per delivery point'), provenance ('returns source and year'), freshness ('latest publishable'), and critically the null semantics ('unavailable is not zero'). Auth requirements and rate limits are not mentioned, which is the main residual gap.

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 capability, followed by the unit caveat and the null-value warning. No filler, and each sentence adds 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?

There is no output schema, and the description compensates by describing the return payload (source and year) and the null-vs-zero distinction. For a single-parameter read tool this is nearly complete; only error behavior for invalid or uncovered commune codes is left unspecified.

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 0%, so the single parameter code_insee is documented only by its name and regex pattern. The description's phrase 'for one French commune' implies the parameter identifies a commune, but it adds no detail on INSEE code format, overseas departments, or what happens on an unknown code — the schema pattern alone carries the format.

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 resource and scope: 'Latest publishable residential gas consumption for one French commune', with a clear unit definition ('Annual kWh per delivery point'). It implicitly separates itself from the electricity sibling by naming gas, and explicitly rules out household-level and address-eligibility interpretations, though it never names the sibling tools it is not.

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 clause 'not household consumption or address eligibility' functions as an explicit when-not, steering the agent away from address-level tools such as search_addresses. What is missing is a positive routing statement naming the alternative tool to use for household-level or electricity questions.

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