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

Annotations already cover readOnly and openWorld, but the description adds material context beyond them: a concrete price ($0.002 USDC per successful call), payment rails, the 'failed calls are not charged' guarantee, and the 'newest page only, no full documents' data limitation. These are exactly the traits an agent needs before spending money on a call.

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?

Two sentences, front-loaded with the resource and returned fields, then the operational constraints and cost. No filler, nothing that could be cut without losing information.

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?

An output schema exists so return values need not be explained, yet the description still names the key fields. Combined with the pagination limit and pricing model, an agent has enough to call correctly; only sibling differentiation 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 description coverage is 100% and the single 'limit' parameter is fully documented in the schema with its range and default. The description adds no parameter-level detail, which is acceptable at this coverage level but earns only the baseline.

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 ('Latest UK public sector tender notices from Find a Tender'), the source format (OCDS release packages), and enumerates the returned fields, so an agent knows exactly what it gets. It does not distinguish itself from the closely related sibling gov_ukcontracts_tenders, leaving that disambiguation to inference.

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?

'Latest ... newest page only; no full documents' implicitly scopes the tool to recent-notice discovery rather than document retrieval. However, no alternative tool is named and no explicit when-to-use/when-not-to-use condition is stated, so the routing guidance is only implied.

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