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

There are no annotations, so the description carries the full behavioral burden. It mentions the endpoint and response contents but doesn't disclose important traits like whether this is a read-only operation, whether slice IDs are UUIDs vs slugs, what happens if the slice doesn't exist, or any pagination/size limits. This is a data retrieval tool, so the lack of safety/error/edge-case context is a meaningful gap.

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 well-structured sentence that front-loads the action and resource, then lists returned fields. It earns its place by specifying the response structure, though the long enumeration of fields could be condensed.

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?

There is no output schema, so the description helpfully enumerates the response fields (as_of, row_count, source, licence, rows with company/call sign/FRN/service/status/dates). For a single-parameter download tool this is mostly sufficient, but it lacks clarity on slice_id format/source and error conditions, and gives no explicit guidance distinguishing from sibling fcc_snapshots.

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 schema defines only slice_id with a pattern and length limits but provides no description. The tool description says 'by slice_id' and implies it identifies a specific snapshot, which adds mild semantic meaning. With only one parameter and pattern constraints present, the schema already carries most of the load, so a baseline around 3 is appropriate.

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 verb ('Download'), a specific resource ('one FCC radio licence snapshot by slice_id'), and identifies the endpoint path. It distinguishes the singular-snapshot operation from sibling tools by explicitly mentioning the slice_id dimension, though it doesn't name a specific sibling alternative.

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 implies the tool is for downloading a specific snapshot when you already have a slice_id, and lists the returned fields. However, it doesn't explicitly contrast with sibling tools like fcc_snapshots (plural) or fcc_search, so an agent must infer when this one is preferred over the others.

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