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

Annotations already cover the safety profile (readOnly, non-destructive, idempotent, non-sensitive), so the description's burden is light. It adds that Open-Meteo is used and that the return is a current temperature, but doesn't disclose request/response behavior or caveats. This is minimal but not contradictory.

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 a single concise sentence with no filler. The main idea is front-loaded and easy to parse, though it could include slightly more operational detail without losing conciseness.

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?

The tool has a noisy seven-parameter schema and no output schema, but the description does not specify required parameters, return units, or how to ignore irrelevant inputs. An agent could be confused by the unrelated parameters and lacks enough information to invoke the tool confidently.

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?

The input schema provides descriptions for all parameters, so the baseline is 3. The description highlights 'city' as relevant, but the schema also lists six unrelated parameters (ref, url, feed, host, json, path) with discard notes; the description does not help the agent understand that only 'city' should be used or that the others are likely irrelevant.

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 concrete function: returns current temperature for a city, and names the source (Open-Meteo). It is unambiguous about the domain, though it doesn't explicitly distinguish it from sibling tools like geo-hint.

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?

No guidance is provided on when to use this tool versus alternatives. It doesn't name sibling tools, conditions, or exclusions. The Open-Meteo reference implies an external weather source, but no usage criteria are offered.

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