xero_update_credit_note

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

Annotations already carry the safety profile (readOnlyHint=false, destructiveHint=true, idempotentHint=true), so the bar is lower. The description adds some useful context beyond annotations: routing through the governed connector authority, that `effect` is caller-claimed and verified by Spring, and that `approval_ref` is needed when resuming a write. However, it does not disclose what destructive consequences the update may have on the credit note (e.g., voiding, amount changes, status transitions). No contradiction with annotations.

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 args list is scannable and each line is terse, earning its place. But the opening sentence is pure redundancy — it restates the tool name and platform path instead of describing functionality, wasting the most prominent position where the actual purpose should be stated. The description is slightly over-long for the semantic content it delivers.

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 write operation with 7 parameters and 0% schema coverage, the description is not complete enough. The governance workflow (routing, effect verification, approval_ref for writes, idempotency) is well covered, but the Xero-domain semantics are absent: what fields can be updated, what the `arguments` JSON should look like, and what the destructive implications are. An agent could manage the auth plumbing but would be guessing at the payload and business effect. The presence of an output schema does not compensate for missing input semantics.

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?

With 0% schema description coverage, the description carries the full burden and does supply meanings for all 7 parameters: project_id, project_ref, connector_account_ref as a 'project-bound connector account alias', idempotency_key as a 'stable business-action identity', and the effect/approval_ref workflow. However, the critical `arguments` parameter — the actual Xero operation payload — is only described as 'JSON string of arguments for the connector operation' with zero guidance on what keys or structure it should contain, which is exactly what an agent needs to invoke the operation correctly.

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 opens by restating the tool name and platform path ('Xero connector operation `update_credit_note` (platform tool `xero.update_credit_note`)') without adding semantics about what updating a credit note actually entails. No mention of which credit note fields or statuses can be changed, what state the record must be in, or what the business effect is. Apart from the verb in the name, the description is a tautology.

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 provides no when-to-use guidance and names no alternatives. It never contrasts with sibling tools like xero_create_credit_note or xero_list_credit_notes, so an agent cannot tell when updating is appropriate versus creating or listing. The 'Routes only through the exact project/account governed connector authority' line is a routing constraint, not a usage guideline.

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