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

Annotations already indicate a non-read-only, idempotent, non-destructive mutation. The description adds meaningful context by saying the operation 'sets or overrides' an existing value, clarifying that the prior value is replaced rather than accumulated or appended.

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 front-loaded, information-dense sentence. Every word contributes: what happens, what is being modified, and that the lead must already exist.

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 simple mutation, clear schema, output schema, and annotations, the description is largely sufficient. The main minor gap is that it does not clarify how the target lead is identified, since the identification parameters are optional in the schema.

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 100%, so the parameters are already well-documented. The description adds only the pipeline context and the overriding semantics, which is useful but not a substantial improvement over the schema.

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 states a clear action ('sets or overrides') with a precise resource and scope ('estimated EUR pipeline value of an existing lead'). It is not a tautology and conveys a distinct purpose among the sibling tools.

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 context is implied: use this when a lead already exists and its estimated EUR pipeline value should be set or replaced. However, the description does not explicitly state when to prefer it over alternatives or when not to use it.

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