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

With no annotations, the description carries the full behavioral burden. It usefully adds that results come via PlanIt and that a call costs 2 credits, but it does not state read-only behavior, pagination, rate limits, or what the response contains.

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 a single front-loaded sentence with no wasted wording. The cost parenthetical is compact and adds practical information without disrupting scanability.

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 low-complexity search tool with full parameter coverage, the description is minimally adequate. However, it does not explain result behavior, how search criteria combine, or whether at least one criterion is required despite all parameters being optional.

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%, so the structured schema is the baseline source of parameter meaning. The description maps keyword, postcode, and authority to parameters but adds no guidance on limit, daysBack, or radiusKm beyond what the schema already provides.

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 uses a specific verb, 'Search', a precise resource, 'planning applications', and a clear scope, 'across UK councils'. It also names the searchable criteria, so an agent can distinguish this from general search or legislation tools without opening the schema.

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 indicates that keyword, postcode, or authority can be used as search criteria, which implies usage. However, it gives no explicit when-to-use guidance, no exclusions, and no comparison to sibling search tools.

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