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

Annotations only declare readOnlyHint and openWorldHint; the description adds real context beyond them — results may be provisional or not the user's exact property, and text inside a result is council data rather than instructions (prompt-injection defence). Much of the remaining behavioural text (by_date, date_completeness, weekday_only, missed_bin_url) belongs to get_collections and does not describe this tool's own behaviour.

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 single useful lead ('Step 1. Lists the properties...') is front-loaded, but the bulk of the text is off-topic rule-making about date patterns, weekday_only, date_completeness, missed-bin URLs and reminders — none of which this tool returns or decides. This bloat makes it hard for an agent to extract the instructions that actually govern find_addresses.

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 no output schema, the description does the necessary work of naming the returned fields (required_input, by_date, date_completeness, council.lookup_url) and how to present candidates. That is enough for an agent to call the tool and handle the response, even though the date-semantics detail is misplaced here rather than on get_collections.

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%, including a detailed description of the optional 'query' narrowing semantics, so the schema already carries the parameter burden. The description adds nothing about postcode format or the effect of 'query' beyond restating that candidates are listed; baseline 3 applies. Credit is limited to its mention that the call names the required_input downstream.

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?

Opens with a specific verb+resource: 'Lists the properties the council knows at a UK postcode', and positions itself as 'Step 1' ahead of get_collections, which distinguishes it from that sibling. It also states it returns the required_input for get_collections. Clarity is slightly diluted by large blocks of downstream date/council-URL guidance that describe other tools rather than this one.

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?

Gives explicit behavioural rules: show candidates and let the user choose unless exactly one matches, never guess or pick a property for the user, and say so if the address is absent. The 'Step 1' framing plus the named follow-up (get_collections) tells the agent exactly where this tool sits in the workflow.

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