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

Annotations cover readOnly/openWorld, and the description adds what they can't: per-call pricing ($0.002 USDC via x402 on Base, Solana or Arc) and the no-charge-on-failure policy. It also discloses the ~20-item cap and that article bodies are absent — exactly the behavioral context an agent needs before spending money.

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?

Three dense sentences, front-loaded with purpose then constraints then cost. The pricing and failure-charge clause is essential rather than padding, so every sentence earns its place.

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 an output schema present, return values needn't be re-explained, yet the description still names the fields. Cost, feed size, and the no-article-body limitation are all covered, leaving no gap an agent needs filled before calling.

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?

Schema description coverage is 100% and the single limit parameter (1–20, default 10) is fully documented there. The description's 'about 20 items' corroborates the ceiling but adds no new parameter-level guidance, so the schema does the heavy lifting.

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?

States a specific verb (retrieves) and named resource (Bloomberg Markets RSS headlines) and enumerates the returned fields: title, short description, link, author, publish time. No sibling covers Bloomberg markets headlines, and the scope is unmistakable.

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?

Clearly frames the boundary: feed-only, ~20 items, article bodies not returned, which tells an agent when this is insufficient. It stops short of naming an alternative sibling (e.g. news_radar or web_search_turbo) for broader or full-text needs, so it is clear context without explicit exclusions.

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