freeagent_update_invoice_status

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

Annotations already signal destructive and non-read-only behavior, but the description adds valuable context: 'no email is sent to the client' and explains what each transition does (e.g., 'issue it', 'pull it back'). This goes beyond the structured data and clarifies a key side-effect that users would otherwise assume. 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?

Two concise sentences front-load the purpose and immediately list the supported transitions. Every word earns its place, and the behavioral note about email is a single clause. No fluff or redundancy.

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?

The tool is a simple mutation with no output schema, and the description covers the core behavior, transitions, and a key side-effect (no email). It could mention prerequisites like invoice state, but the description is sufficient for most use cases given the tool's simplicity.

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%, so baseline is 3. The description adds meaning beyond the schema by explaining the transition enum values in plain language (mark_as_sent = issue it, mark_as_draft = pull it back), which helps the agent select the right transition. This elevates it above the baseline.

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 the tool changes an invoice's status, enumerates the exact transitions (mark_as_sent, mark_as_draft, mark_as_scheduled, mark_as_cancelled), and explains their effects. This distinguishes it from sibling invoice tools like list_invoices or get_invoice which don't modify status.

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 implies when to use the tool: whenever an invoice's status needs to be changed. It doesn't explicitly mention alternatives or exclusions, but the scope is unambiguous given the sibling context. A clear 'use this instead of X' would push it to 5, but it's still well-contextualized.

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