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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds substantial behavioral context beyond annotations: the ~3h latency, the regional (non-global) ingest coverage, the shallow archive caveat, the meaning of a detection as a hot pixel rather than a confirmed fire, and the explicit warning that absence of detection does not mean absence of fire. It also discloses that every response carries a coverage block and instructs the agent to read it before characterizing zero results.

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 long but every sentence earns its place: it covers mode selection, interpretation rules, coverage caveats, and parameter semantics. The critical interpretation rules are clearly marked with 'CRITICAL INTERPRETATION RULES' and the coverage warning is front-loaded enough to be noticed. It could be slightly tighter, but the density of essential guidance justifies the length.

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 12-parameter tool with no output schema, the description is remarkably complete. It explains both modes, the return fields for facilities mode, the coverage block semantics, the interpretation pitfalls, and the regional limitation. The only minor gap is that it doesn't describe the exact return shape for raw mode, but the schema and the mode descriptions make this inferable, and the interpretation rules are more important for correct use.

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 100%, so the baseline is 3. The description adds value by grouping parameters by mode (facilities vs raw), explaining the default behavior of min_detections (default 1, pass 0 to include quiet facilities), and clarifying that country names are full English not ISO codes. It also explains the meaning of FRP in context. However, it doesn't add much beyond the schema for lat/lon bounds or limit, which the schema already documents adequately.

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 ('Query') and a precise resource ('NASA FIRMS satellite thermal anomalies'), names the two data products (VIIRS 375m + MODIS 1km), and immediately distinguishes the two modes. It clearly differentiates itself from siblings like query_refineries and query_power_plants by focusing on thermal anomaly detections rather than static infrastructure.

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 gives explicit when-to-use guidance for both modes: mode='facilities' for facility-centric questions with concrete example queries, and mode='raw' for geographic questions not anchored to a monitored facility. It also provides critical interpretation rules that tell the agent when NOT to attribute detections to strikes or fires, and how to handle zero results via the coverage block.

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