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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint=false, so the safety profile is covered. The description adds useful behavioral context: it returns archive coverage per sensor/stream and is intended as a pre-flight check to avoid misreading empty hotspot results. It does not add auth or rate-limit details, but those are largely covered by the schema.

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, front-loaded with the tool's purpose and followed by the concrete usage scenario. Every sentence earns its place with no redundancy.

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 metadata/availability tool with 100% schema coverage and no output schema, the description is complete enough. It explains what is returned (first and last date per sensor, for NRT and standard streams) and why an agent should call it, so nothing critical is missing.

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 source and _apiKey parameters are already fully documented in the schema. The description implies per-sensor coverage but adds no syntax or filtering detail beyond what the schema provides. Baseline 3 is appropriate when the schema does the heavy lifting.

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 specific resource and scope: which dates each NASA FIRMS satellite product covers, first and last available date per sensor, for near-real-time and standard-processing streams. It clearly distinguishes this metadata tool from the hotspot-query siblings by framing it as a pre-check.

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?

Explicitly tells the agent to call this before querying a historical date so empty hotspot results can be interpreted correctly. It gives clear context and a motivating scenario, but does not name the alternative hotspot tools directly or list exclusions.

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