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

Annotations already cover readOnly, idempotent, non-destructive and closed-world, so the safety profile is done. The description adds genuinely non-derivable behavior: IRD and bank account numbers are never included in results, and pagination is capped at 500 with a defined response shape (items, total, offset, limit). It does not describe ordering or error behavior, but the added disclosure is substantial.

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?

It is one dense, front-loaded block covering resource definition, exclusions, id usage, ambiguity handling and pagination with no filler sentences. The long run-on structure across multiple concerns slightly hurts scanability, but every clause earns its place.

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?

There is no output schema, and the description compensates by naming the returned fields and the pagination envelope (items, total, offset, limit). Combined with the 100%-covered input schema and full annotation set, an agent has everything needed to call and interpret this tool.

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 all five parameters are already documented in the schema. The description adds only marginal meaning ('search by part of the name', the 500-page cap), repeating the schema's own guidance on paging and default limit. Baseline 3 is appropriate when the schema does the heavy lifting.

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?

States a specific verb and resource ('Finds the organisation's contacts') and then defines the resource concretely (suppliers, tenants, contractors, property owners, landlords, accountants) with the fields returned. This clearly separates it from create_contact, update_contact and list_contact_types in the sibling set.

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 operational guidance: use the returned ids with other tools, search by part of the name when a person names a contact, and when matches are ambiguous or absent show the closest and ask rather than guessing an id. This is when-to-use plus a when-not behavior (never guess an id) that an agent must follow.

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