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

With no annotations, the description carries the full burden of disclosing behavior, but it only states the output ('current temperature') and data source ('Open-Meteo'). It does not mention side effects, failure modes, rate limits, network dependence, or whether the operation is read-only. The schema mismatch also obscures what the tool actually does with its parameters.

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 unnecessary wording. It front-loads the primary purpose and data source. However, it is so terse that it omits important contextual information, though that is more a completeness issue than a conciseness issue.

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?

Given the tool has nine optional parameters, no output schema, and no annotations, the description is severely incomplete. It does not explain which parameters are relevant, how they map to the city temperature lookup, what the response format is, or what happens when parameters are omitted. The unrelated parameter descriptions add confusion rather than completing the 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?

Although every parameter has a schema description, those descriptions are generic and largely inconsistent with the stated purpose. Parameters like ref, url, feed, host, json, path, zone, and query appear unrelated to returning a city temperature, and their descriptions use template phrases like 'discarded after the shape check' or 'no disk access'. The city parameter description even says 'discarded after the call', which contradicts the tool's purpose.

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 clearly indicates the tool returns the current temperature for a city using the Open-Meteo service. It is specific enough to distinguish a weather lookup from general fetching or time-related tools. However, it is phrased as a noun phrase rather than an explicit verb like 'get' or 'retrieve'.

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 usage guidance is provided about when to prefer this tool over siblings such as geo-hint, timezone, or web-fetch. The description does not mention required inputs, typical invocation scenarios, or when not to use it. This leaves the agent without actionable direction beyond the bare purpose.

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