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

With annotations present, the description adds real value: it explains that destructiveHint=false because the action is simulated pending approval, and that manage_action is the confirmation path. It also discloses the 'Demo invoicing (sample data)' scope, which is important behavioral context not encoded in the 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?

Front-loaded with the bracketed '[Invoicing changes]' tag, then the core action, then the approval/simulation caveat, then the environment scope. Three compact sentences with little waste, though the parenthetical '(asked in the conversation, confirmed with manage_action)' is slightly dense.

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?

An output schema exists, so return values need not be described. The description covers the proposal/simulation semantics, the approval path, and the demo-data scope, leaving only minor gaps (no error or edge-case behavior) for a 4-param tool.

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 25% — only 'account' is documented. The description names the doc types ('invoice or proforma') matching doc_type's enum but gives no meaning for 'series' or 'number', nor their expected format, so it does not compensate for the coverage gap.

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?

States a specific verb and resource ('Propose cancelling an issued invoice or proforma'), clearly scoping it as a cancellation proposal and naming the document types. This distinguishes it at a glance from invoices_issue, invoices_get, and invoices_list.

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?

Explains the workflow: it is simulated first, nothing changes until the seller approves, approval is asked in conversation and confirmed with manage_action. That tells the agent when and how to use it, though it doesn't explicitly contrast against sibling alternatives like invoices_get or orders_attach_invoice.

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