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

With no annotations, the description carries the full burden and does so thoroughly: it discloses the URN join, data provenance from daily GIAS and monthly Ofsted extracts, that head-teacher names and phones are dropped, that governors data is never ingested, and the filter combination behavior. This goes well beyond what the schema provides.

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 long but information-dense, front-loading the resource scope and available fields before moving to provenance, exclusions, and usage rules. Every sentence contributes meaning without filler.

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?

For a 22-parameter query tool with no annotations and no output schema, the description is unusually complete: it covers coverage, data sources, join logic, dropped fields, filtering behavior, and cost. Minor gaps remain in describing pagination defaults and exact response shape, but those are partially inferable from the schema defaults and tool name.

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 0%, and the description compensates substantially by enumerating filterable fields that map to most parameters: URN, name, type/phase, status, local authority/region, address/postcode, pupil counts, trust, and Ofsted rating/date. It also clarifies q and AND semantics, though it does not explicitly document every parameter such as page, per_page, outward_code, or website_present.

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 precisely identifies the resource: every school, academy, college, and nursery on the DfE register joined to Ofsted data, scoped to England. It lists the key fields returned, making the tool's purpose unmistakable and clearly distinct from sibling UK-domain query tools.

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 gives concrete usage semantics: 'Filters combine with AND; q searches all text fields' and notes the cost of 1 credit per call. It does not explicitly discuss alternatives, but the sibling tools cover different UK datasets, so the context is clear enough without exclusions.

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