Create a ProAbono customer (write)

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

With no annotations, the description must carry behavioral disclosure. It clearly marks the operation as a write and explains the upsert semantics, which is critical behavior. However, it doesn't address authorization requirements, reversibility, or what happens to existing fields on update, leaving some 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?

The description is efficiently structured, starting with a 'WRITE.' marker, then the core purpose, then the upsert detail, then the recommendation. Every sentence adds value and the key information is front-loaded. It is a bit longer than minimal but remains focused.

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 tool with 5 parameters, no output schema, and no annotations, the description covers the essential context: the upsert nature, the recommended usage timing, and the dependency on hosted pages. It doesn't describe the return value, but that's often not needed for calling. The description plus schema is sufficient for correct invocation.

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%, with all parameters already described in the schema. The description adds context about the customer_ref being derived from the application's user identifier (already in schema) and mentions the Segment, but doesn't enhance parameter meaning beyond 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 specific verb ('Creates'), resource ('ProAbono customer'), and context ('in the configured Segment, keyed by the reference'). It also distinguishes itself from update_customer by explicitly noting the upsert behavior, making the tool's role clear even without inspecting siblings.

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?

It provides a clear recommendation for when to use the tool ('at sign-up or first login') and explains why (hosted pages and rights read need the customer). It implies this is the primary write path by describing the upsert behavior, though it doesn't explicitly name alternatives like update_customer.

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