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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered, and the description adds genuinely non-obvious context: it is a public feed needing no key, each successful call costs $0.002 in USDC via x402 on Base/Solana/Arc, and failed calls are not charged. That payment/failure-charging detail is exactly the kind of behavioral trait annotations cannot express. It stops short of rate limits, pagination, or what 'latest' concretely means in time.

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?

Four dense sentences with zero filler: source and scope first, then freshness, then auth, then cost. The telegraphic style ('Public feed, no key.') delivers maximum information per token and the most decision-relevant constraint (paid per successful call) is not buried.

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 two-optional-param read tool with an output schema, the description covers scope, freshness, auth, and billing, which is close to complete. The remaining gaps are the undefined recency window behind 'latest items only' and the absence of any routing versus the sibling PR-wire tools.

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%, with both q (max 200 chars, all words must appear in title or summary) and limit (1-30, default 10) fully documented in the schema. The description adds only the redundant note that filtering is on title/summary, so the baseline 3 applies.

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 a specific resource with a narrowing scope: PR Newswire press releases in the health category, pulled from its public RSS feed with a keyword filter on title/summary. That is meaningfully more specific than a tautology, but it never distinguishes itself from the sibling tools search_pr_newswire and search_press_release_multi_wire, so an agent cannot tell from the description alone whether this is the narrower or broader wire tool.

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?

Usage is only implied: 'Latest items only' signals recency scope, and 'keyword filter on title/summary' signals how to search, but there is no explicit when-to-use or when-not-to-use statement. Crucially, no alternative is named – the sibling search_pr_newswire is an obvious substitute and the description gives no rule for choosing between them.

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