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

Annotations only supply destructiveHint=true and a title, so the description usefully adds that this is a PATCH-style partial update where unspecified fields are untouched, plus the raw endpoint. It says nothing about reversibility, permissions, or any error/not-found behavior for a destructive mutation, leaving real gaps.

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, front-loaded with the action, then the partial-update rule, then the endpoint. Every sentence carries information and there is no filler.

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 destructive partial-update tool with no output schema, the description covers the essential mechanics: what it mutates and that omitted fields are preserved. It omits permission requirements and failure/return behavior, which are the remaining meaningful gaps.

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%, so the schema already documents all nine parameters including stage examples, micros/currency semantics, and the extra passthrough object. The description adds no parameter-level meaning beyond that, 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?

States a specific verb (update) and resource (opportunity) plus the partial-update behavior and the underlying endpoint (PATCH /rest/opportunities/{id}). The verb alone distinguishes it from create/get/list/update siblings, but it never names an alternative explicitly.

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?

Usage is implied by 'update fields on an existing opportunity' and 'only provided fields change,' which tells the agent this is a partial rather than full replacement. There is no statement of when to prefer this over create_opportunity, and no prerequisites such as required permissions or a prerequisite that the record exist.

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