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

With no annotations, the description carries the disclosure burden. It partially meets it by naming the return shape (id, name, defaultCategoryId, aggregated stats) and the read-only listing semantics implied by 'List'. It stops short of stating pagination, result limits, or sort order — material omissions for a list endpoint with no output schema.

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?

Two sentences with no filler, front-loaded with the verb and resource, then the filter, then the return shape in a parenthetical. The return enumeration is slightly dense but each clause carries distinct information.

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 one-parameter list tool with no output schema and no annotations, the description supplies the purpose, the filter semantics, and the return fields, which is the bulk of what an agent needs. The remaining gaps are pagination/limits and explicit sibling routing, both minor but non-trivial.

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%: the single 'q' parameter is already documented in-schema as a substring filter on the normalized payee name. The description adds only the word 'optional' beyond the schema. Baseline 3 applies 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 ('List Payees') and disambiguates the domain term by defining a payee as 'merchants/counterparties for the user'. It also enumerates the returned fields, so an agent knows this is a bulk-listing read. It does not explicitly contrast with the sibling 'get_payee' (singular), leaving that differentiation to inference.

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 notes the filter is 'optional' and applied as a 'substring query', which implies the no-arg path lists everything. However, there is no explicit when-to-use guidance and no mention of the sibling tools an agent might reach for instead (get_payee for one payee, merge_payees for consolidation). Usage is implied rather than stated.

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