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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so safety behavior is covered structurally. The description adds meaningful context beyond that: the data is 'AUTHORITATIVE ... straight from the catalogue,' which tells the agent to trust this over inference. It does not mention caching, rate limits, or error behavior for unknown ids, so it falls short of a 5.

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 tight sentences, each doing distinct work: what it returns, why to trust it, and when to call it. The return-field enumeration is front-loaded ahead of the usage routing.

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?

No output schema exists, but the description enumerates the returned payload (title, description, licence, providers, spatial/temporal extent, asset keys), which is precisely what an agent needs to decide whether to call it. Nothing material is missing for a single-parameter lookup tool.

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?

One parameter with 100% schema coverage, so the schema already carries the format and examples. The description still adds value by specifying that ids must be sourced from planetary_computer_collections, closing the loop on where collection_id values legitimately come from.

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 verb and resource ('Full detail for one Planetary Computer collection') and enumerates exactly what it returns — title, description, licence, providers, extent, asset keys. An agent can distinguish it from planetary_computer_collections (list) and planetary_computer_search (items) without opening either schema.

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?

Gives explicit sequencing guidance: 'Use it before planetary_computer_search to learn the band names you will get back' and 'Get valid ids from planetary_computer_collections.' Both the when and the prerequisite source for valid inputs are named.

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