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

Beyond readOnlyHint/openWorldHint it discloses ordering ('newest first'), coverage limits (announced completed deals only, live mandates absent), and a paid-call model: $0.002 USDC via x402 on Base, Solana or Arc with failed calls not charged. That billing and failure-charging detail is exactly the context an agent cannot infer from 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?

Front-loaded with the resource and payload, with no filler sentences. The single long colon-plus-semicolon construction is dense but every clause carries information an agent needs, so it is only slightly less scannable than an ideal version.

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?

Output schema handles return shape, and the description still previews the fields; payment mechanics, ordering, and coverage caveats are all present. For a two-optional-parameter read tool, nothing an agent needs before calling is missing.

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 coverage is 100%, so the baseline is 3, but the description adds real meaning by naming what the keyword matches against (company, country, sector) and confirming the newest-first ordering. It does not restate the limit bounds, which the schema already carries.

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 and resource ('Recent M&A deals closed by Benchmark International') and then enumerates the exact payload (target, acquirer, deal summary, announcement link). No sibling in the list covers M&A deal flow, so the tool is unambiguous against the directory/registry tools around it.

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?

Gives an explicit inclusion/exclusion rule: 'Only announced completed transactions; confidential live mandates are not public,' and describes the optional keyword filter with its matching dimensions. It does not name an alternative tool or state when a different source would be better, which keeps it short of a 5.

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