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

Annotations only declare readOnlyHint, so the description carries the rest: it discloses a size ceiling (~700 tokens), that freshness and source health are reported, and the cross-tool pattern for drilling into any item. That is unusually rich behavioral context for a read-only summary tool.

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?

Roughly 90 words with the content summary front-loaded and the exclusion stated before the mechanics. The trailing sentences on token budget, fetch drilling and omitted items are useful but hop between topics, and the `pointrover_brief({})` example is filler given the empty schema.

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?

With no output schema, the description enumerates what comes back, notes freshness and source status, and explains how to reach anything not included. For a zero-parameter orientation tool, an agent has everything it needs to call it and act on the result.

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?

Zero parameters, so the baseline is 4; the schema already forbids additional properties. The description confirms 'Takes no parameters' and shows a literal call example, which is mildly redundant against the empty schema but harmless.

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 names the resource (a single business brief) and enumerates its contents: upstream movements, open tariff alerts, events, upcoming rules, and last-checked freshness. That is specific enough to distinguish it from the granular siblings (pointrover_events, pointrover_series, fetch), though the opening clause is wordy rather than a crisp verb+object.

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 states explicit when-to-use triggers (getting up to speed before planning a purchase, preparing for a supplier meeting, reviewing the month) and an explicit exclusion: the business's own books live in the accounting connector, not here. It also routes follow-up work by noting every item opens with fetch and that omitted items are named with their returning tool.

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