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

With no annotations, the description bears full burden. It discloses key behaviors: sources are limited to 5 public pages plus Wikipedia, facts are dropped if quotes aren't found verbatim, and the output is informational only. It also discloses pricing and payment method, which is useful. However, it doesn't mention rate limits or error handling, but the core behaviors are covered.

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 two sentences, front-loaded with the core purpose and output format, then adds constraints and pricing. Every sentence carries critical information; there is no fluff. It is appropriately sized for the complexity.

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?

Given the tool's moderate complexity with 3 parameters and no output schema, the description covers the essential behavioral details: citation format, source limits, verbatim constraint, and cost. It lacks explicit output schema but there isn't one, and the description implies the return value is Markdown. Minor gaps like error handling are acceptable given the detail provided.

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 description coverage is 100%, so all three parameters are already well-documented. The description adds context that 'topic' is a phrase, not a URL, and that 'sources' are in addition to Wikipedia. However, it does not elaborate on the meaning of 'max_words' beyond the schema, so the value-add is moderate, warranting the baseline 3.

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 verb 'brief' with a specific resource ('any topic') and details the output format (150-500 words of Markdown with citations). It distinguishes itself from siblings by mentioning the citation and verbatim quote mechanism, which is unique among the listed tools.

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 provides implicit usage context: when you need a sourced brief with citations and verbatim quotes. It does not explicitly state when to prefer this over siblings like scrape_summary or yield_report, but the citation requirement sets it apart. There are no exclusions or alternative mentions, so guidance is minimal.

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