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

Annotations already declare the mutation profile (readOnly false, destructive false, non-idempotent). The description adds real behavioral value beyond that: submission routes into a business approval flow, organization-configurable MCP approval requirements, and that business approvals always apply — important context for a non-destructive but state-changing operation.

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?

Three short sentences with the scoping and caveats front-loaded; nothing redundant and every clause carries meaning.

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 needn't be explained. But for a nested-parameter mutation tool with 0% schema coverage, the description leaves the payload structure and field meanings entirely undocumented.

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 0% on a nested object ('data') with entityId, notes, and entityType. The description mentions none of these, so it does not compensate for the missing field-level documentation beyond the self-evident const 'invoice'.

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+resource: 'Submit an existing invoice to the configured business approval flow.' The added 'Does not approve it' clarifies the action's boundary against the decide_/cancel_ invoice approval siblings, though it doesn't name them directly.

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 line 'Does not approve it' implicitly steers an agent away from decide_invoice_approval_request, and the workflow note implies MCP vs business approval layers. However, no siblings are named and no explicit when-to-use/when-not conditions or prerequisites are given.

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