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

Annotations already declare mutating (readOnlyHint=false) but non-destructive and closed-world, so the safety profile is covered. The description adds real context beyond that: the closure is 'credited to the person this connection acts for' — a side effect on attribution — and that it targets the Needs-you surface. It omits recovery/idempotency behavior if the request is already closed.

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, zero filler, with the action front-loaded and the qualifier and attribution trailing. Nothing to cut.

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 2-param mutation with full schema coverage and no output schema, the description covers purpose, context and the attribution side effect adequately. What's missing — behavior when no open request exists, or what the response returns — is minor but real.

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% and both parameters (brand, contact) are documented with sourcing hints (get_overview brands[].slug, list_chats/list_needs_you/search_chats). The description adds no meaning beyond this, so the baseline 3 applies.

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?

Specific verb+resource: closing 'the chat's open request in Needs you', which maps to a concrete feature surface (list_needs_you) and is distinct from every sibling (no other close-style tool exists). An agent can immediately tell what state-changing action it performs.

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?

'for work settled by a call or in person' gives an explicit usage context (off-channel resolution) rather than an arbitrary trigger. It stops short of naming a when-not or an alternative tool, so the guidance is clear but not exhaustive.

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