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

Annotations already mark readOnly and idempotent; the description adds dynamic context like 'RIGHT NOW' and 'coverage deepens daily toward the backfill horizon,' revealing that data evolves over time. It also discloses the access tier component, adding value beyond annotations.

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 'Orientation,' and every clause adds value: scope, temporal dynamics, access tier, examples, and when to use. No redundancies or filler.

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 zero-parameter orientation tool with no output schema, the description fully covers purpose, content, and usage context. It also indirectly orients the user to sibling tools via 'example question per 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?

With zero parameters, the baseline is 4. The description compensates by explaining what the tool returns (date ranges, access tier, example questions), which is sufficient given no schema to elaborate on.

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 states the tool is an orientation that reports live per-feed date ranges, access tier, and example questions per tool. It uses a distinct verb 'describe' and positions itself as a first-call tool, differentiating it from the data-query siblings.

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 instructs 'Call this first when unsure what to ask or whether a date range is covered,' providing direct when-to-use guidance and implying it should precede sibling queries. This is clear and actionable.

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