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

Annotations already declare destructiveHint=true, openWorldHint=true and idempotentHint=false, so the safety profile is covered structurally. The description adds nothing behavioral: no mention that creates are non-idempotent (duplicate submissions create duplicate opportunities), no note on the destructive flag, no confirmation of what number/ID is generated.

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?

One sentence, front-loaded with the action and resource, zero filler. It is efficient but arguably too thin for a 12-parameter creation tool.

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 12-parameter mutation with no output schema and low schema coverage, the description omits what a successful call returns (opportunity ID), defaults behavior for stage/score/project_type, and any error conditions. It is not sufficient on its own.

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 only 33%, so the description should compensate but only names stage, score, budget and expected sale date; it ignores project_type, number, address fields and the customer_id contact_id nuance, which is documented only in the schema. It adds some field-level meaning but leaves half the parameters opaque.

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?

Clear verb+resource: 'Adds a sales opportunity for a customer', with the main fields enumerated. It is distinguishable from creation siblings such as create_lead or create_project by resource name alone, though it never explicitly contrasts with them.

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?

There is no guidance on when to create an opportunity versus a lead, project, or estimate, and no prerequisites beyond the implied customer. An agent must infer the routing decision entirely from the tool name.

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