Search GOV.UK

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

Annotations already declare readOnlyHint=true, destructiveHint=false, idempotentHint=true. The description adds value by stating it returns 'title, description, link, format, owning organisation(s), and last updated timestamp,' and mentions pagination via start parameter. No contradiction.

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?

Three short paragraphs, front-loaded with main action. Every sentence adds value: what it searches, what it returns, how to filter. No redundancy or fluff.

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 6 parameters (1 required), 100% schema coverage, and an output schema (not shown but referenced), the description sufficiently covers search usage, output shape, and filtering. It is complete for an agent to select and invoke correctly.

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% with descriptions for all parameters. The description adds meaning beyond the schema by providing concrete examples for filter_format (e.g., 'transaction' for citizen-facing services) and filter_organisations (e.g., 'hm-revenue-customs'), and clarifying sort order syntax.

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 it searches GOV.UK's 700k+ content items using the official Search API. The title 'Search GOV.UK' and description explicitly distinguish this from sibling tools like govuk_get_content (for specific items) and govuk_grep_content (grep-like).

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 guidance on when to use filters: 'Use filter_format to narrow to specific content types' and 'Use filter_organisations to restrict to a department.' It does not explicitly exclude alternatives but implies this is for general search, while siblings serve different purposes.

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