update_customer

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

No annotations are provided, so the description carries the full burden. It does an excellent job: discloses that currency here is the customer's *default* trading currency for future documents (not retroactive), that 'false' for active archives without deleting, and that address merges onto existing (with empty string to clear). These are non-obvious behavioral nuances beyond the schema.

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?

Well-organized as a top-line summary followed by an Args block. Each parameter gets a compact bullet. Slight redundancy with the notes parameter already having a schema description, but the functional trade-off is minor given the poor overall schema coverage. No wasteful 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 6-parameter mutation tool with no annotations and only 17% schema coverage, this description is thorough. It covers all parameters, explains mutation semantics, archival behavior, currency non-retroactivity, and address merging. An output schema exists so return-value detail isn't needed. This is comprehensive for the complexity level.

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 17%, so the description must compensate. It adds meaning to essentially every parameter: id format example, currency notation ('default' trading currency), notes clearing semantics ('Pass "" to clear'), active deactivate/reactivate meaning, and address partial-merge behavior with sub-field clearing. This significantly exceeds what the sparse schema provides.

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 clearly states 'Update an existing customer' with specific verb+resource. It specifies the partial-mutation semantics ('Mutates only the fields supplied; everything else stays') and distinguishes this from the create_customer sibling by focusing on updating rather than creating.

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 description explains the partial-update semantics clearly ('Mutates only the fields supplied; everything else stays'). However, it doesn't explicitly name alternatives or state when not to use this tool versus create_customer/update_vendor/update_employee, though the intended usage context is reasonably inferable.

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