Set a customer's lead source

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

Annotations already declare non-readOnly, non-idempotent, non-destructive. The description adds value beyond them by disclosing where the value lives (on the customer, not the job) and that every booked job counts toward that source—semantics an agent cannot get from annotations. It stops short of describing overwrite behavior for an existing source or any error conditions.

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 short sentences, front-loaded with the action and followed by the one piece of scope context that matters. 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 two-parameter mutation with no output schema, the description plus schema covers what an agent needs to invoke it correctly. Minor gaps remain about error behavior for an invalid source and whether an existing source is replaced or appended.

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%; sourceName even points to get_business_context jobSources and get_reference_data. The description adds no syntax or format detail beyond the schema, so the 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 names a specific verb+resource (set the customer's lead source) and clarifies the scope as customer-level attribution rather than job-level, which helps separate it from job-oriented siblings. It doesn't name an explicit alternative tool, so it falls just short of a 5.

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 only implied: the reader infers this is the tool for assigning or correcting a customer's attribution. There is no explicit when-to-use vs. when-not, no prerequisites, and no routing to a sibling for the job-level equivalent.

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