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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds the 'read once' guidance and implies the data is stable enum-like values, but it does not disclose further runtime behavior such as whether the response can change after integration or whether authentication is required. Given the strong annotation coverage, a 3 is appropriate.

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?

A single information-dense sentence followed by one clear usage directive. The list of returned categories is front-loaded, and every phrase earns its place; there is no filler, repetition, or unnecessary detail.

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 parameterless, read-only metadata endpoint, the description covers what data will be returned and when to call it. It does not provide an exact response shape or field names, but the absence of an output schema and the 'enums' framing make the category list sufficient for integration purposes.

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 tool has zero parameters and an empty input schema, so there is no parameter semantics to document. Per the baseline for parameterless tools, the description correctly focuses on what the response contains rather than input handling.

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 identifies the tool as a platform metadata/capabilities endpoint by listing the exact categories of data it returns: content formats, content pillars, caption platforms, video statuses, and available scopes. It is more informative than the title and distinguishes itself from the entity-specific sibling tools, though it stops short of an explicit retrieval verb like 'returns' or 'gets'.

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?

It explicitly says when to call the tool: 'Read this once at integration time instead of hardcoding enums.' This conveys both timing and rationale, and the 'instead of hardcoding' phrase gives clear intent. It doesn't discuss when not to use it, but no sibling tool appears to overlap with a global capabilities endpoint.

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