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

No annotations are provided, so the description carries the full behavioral burden. It usefully discloses the cost ('3 credits'), which is real context an agent needs before calling, but says nothing about result volume, ordering, pagination, or whether an empty result set is possible for over-narrow filters.

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?

A single sentence front-loads the resource and scope, then lists the filter axes, with the cost callout appended in parentheses. Nothing is redundant and no sentence is wasted.

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 8 all-optional parameters, full schema coverage, and no output schema, the description covers enough for correct invocation. It omits default values (e.g. limit/daysBack defaults) and what a result record looks like, which would matter for a search tool returning structured listings.

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 baseline is 3, but the description adds genuine meaning by expanding opaque schema tokens: 'fts|cf' is explained as Find a Tender vs Contracts Finder, and 'both' is clarified as the valid stage option. Value range and days-back are mapped to their purpose rather than restated as raw types.

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 ('Search UK public sector tenders and contract awards') and names the underlying data sources (Find a Tender, Contracts Finder) plus the supported filter axes. It largely distinguishes itself from the closest sibling eu_tenders by the explicit 'UK public sector' scoping, but never names that alternative outright.

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 enumerated filters ('keywords, stage, value range, buyer, days back') imply when the tool is appropriate, i.e. any keyword/date/value-scoped tender lookup. There is no explicit when-to-use vs eu_tenders guidance, no statement about combining filters, and no exclusions or prerequisites.

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