govuk-mcp

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

Annotations already declare readOnlyHint=true, destructiveHint=false, idempotentHint=true, and openWorldHint=true. The description adds valuable context beyond annotations: it discloses the scale ('700k+ content items'), return format details ('title, description, link, format, owning organisation(s), and last updated timestamp'), and API source ('official Search API'), enhancing behavioral understanding without contradictions.

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?

The description is front-loaded with the core purpose, followed by return details and usage tips in three concise sentences. Each sentence adds value: the first sets scope, the second outlines outputs, and the third provides filter guidance, with zero wasted words.

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?

Given the tool's complexity (search with multiple filters), rich annotations, 100% schema coverage, and presence of an output schema, the description is complete. It covers purpose, scale, returns, and filter usage, leaving parameter details to the schema and output details to the output schema, making it fully adequate.

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%, providing detailed parameter documentation. The description adds minimal semantics beyond the schema, mentioning 'filter_format' and 'filter_organisations' with brief examples but no new syntax or format details. This meets the baseline for high schema coverage.

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 clearly states the tool's purpose: 'Search GOV.UK's 700k+ content items using the official Search API.' It specifies the verb ('Search'), resource ('GOV.UK's 700k+ content items'), and distinguishes from siblings like 'govuk_grep_content' by mentioning the official API and content scope.

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 description provides clear context for when to use specific filters ('Use filter_format to narrow to specific content types... Use filter_organisations to restrict to a department'), but does not explicitly state when to use this tool versus alternatives like 'govuk_grep_content' or 'list_resources'. It offers practical guidance without naming exclusions.

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