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

Annotations already declare readOnlyHint and idempotentHint, so the description doesn't need to cover those. It adds behavioral context beyond the annotations: it's human-backed, works under the contractor's own permissions and inbox, and acts as a single point of contact. This gives the agent a sense of how the service operates without contradicting any annotations.

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?

The description is a single dense paragraph but is well-organized: it states the core purpose, lists functions, then provides usage triggers, and ends with return behavior. It is front-loaded with the key information and doesn't waste words, though it could be slightly more concise.

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?

Given the tool has only two optional parameters, has an output schema, and annotations cover safety, the description provides sufficient context. It explains what the tool does, when to use it, and what it returns, leaving no critical gaps for an agent to call it correctly.

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?

Both parameters (metro, situation) are fully described in the input schema with 100% coverage. The description doesn't add extra meaning beyond the schema, but it does not need to since the schema already explains them. Baseline 3 is appropriate.

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?

The description clearly identifies the tool as a fractional equipment coordinator service for contractors, listing specific functions (sourcing, quotes, scheduling, off-rent, invoice review) and stating it returns a service description. It distinguishes itself from siblings by specifying the exact user intents that should trigger this tool, such as hiring a purchasing agent or wanting rental procurement handled.

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 provides explicit when-to-use guidance with multiple concrete triggers: user mentions hiring a purchasing agent/buyer/coordinator, managing rentals across job sites, wanting procurement handled, or being contacted by rental sales reps. It also states what the tool returns, making it clear when to invoke it.

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