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

Annotations already declare the safe read-only, idempotent profile, so the bar is lower; the description still contributes a genuinely non-obvious behavioral rule — amounts are bare numbers and get_organization_settings must be consulted for currency_code before reporting a value. That cross-tool dependency is exactly the kind of context annotations cannot carry.

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?

Three short sentences, no filler: purpose first, filtering second, the currency caveat last. Every sentence carries information an agent would otherwise have to guess.

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 filter-only list tool with no output schema, the definition covers what it returns conceptually and the pagination model (all pages auto-fetched, already in the schema), plus the currency pitfall. Nothing essential is missing, though it stays silent on result shape and ordering.

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 page, per_page, search, and category are all documented in the schema itself; baseline 3 applies. The description adds only the mapping of the two filters, and its 'search by title' phrasing diverges slightly from the schema's 'Search by name', which could confuse the agent without adding real semantic depth.

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 concrete verb+resource ('List vendor contracts') and immediately names the two supported access modes (category filter, title search). An agent can distinguish this from siblings such as list_contract_documents, list_contract_sites, and get_contract_document without opening any 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 says how to narrow results (by category, by title) but never states when to prefer this tool over alternatives like a contract detail getter, nor any prerequisite or exclusion. Usage is implied by the filtering capabilities rather than explicitly scoped.

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