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

Annotations already cover safety (readOnly, idempotent, non-destructive, closed-world), so the remaining burden is on describing the payload, which the description does: ids, counts, and invitation context such as shipment or part number. It stops short of noting whether the list is exhaustive or permission-scoped, cost, or ordering.

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, front-loaded with the action and scope, then the routing directive. Every clause carries information (resource definition, returned fields, sequencing guidance) with no restatement of the title or annotations.

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 parameters and full annotation coverage, the only real gap is the return shape, which the description partially covers by naming ids, counts, and invitation context. Small omissions (empty-result behavior, whether all businesses appear) keep it just under fully complete.

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?

The tool takes zero parameters, which is the baseline-4 case; there is nothing for the description to disambiguate. The text usefully reinforces that the scope is implicit — the calling user — rather than parameterized.

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?

"List the businesses (suppliers) that share documents and approved answers with this user" gives a specific verb plus resource and defines the exact scope (user-linked businesses), which cleanly separates it from get_documents and answer_questions. It also previews the returned fields (ids, counts, invitation context).

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?

"Call it first when you do not know which business the user means or need a business_id" states both the triggering condition and the precedence relative to siblings, and implicitly excludes the case where the business is already known. No inference is required to route here.

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