Get invoice

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

Annotations already declare readOnlyHint: true, so the read-only nature is covered. The description adds value by stating the payload includes line items and totals, but it doesn't disclose other behavioral aspects such as error handling or pagination. Given annotations cover the safety profile, the description adds some but not rich context.

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 description is a single, concise sentence that front-loads the action and resource. It is efficient with no redundant wording, though it could include a bit more context without losing conciseness.

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 simple read operation with 2 parameters and no output schema, the description provides enough to understand the core function and return content (line items/totals). However, it doesn't mention the optional locationId or any prerequisites/error semantics, so it's adequate but not exceptionally complete.

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 50% (locationId is described, invoiceId is not). The description says 'by id' which indirectly maps to invoiceId, but it adds no detail about invoiceId format or semantics, and makes no mention of the optional locationId parameter. It only partially compensates for the schema gap, leaving ambiguity.

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 verb 'Fetch' and resource 'single invoice by id', specifies it includes line items and totals, and implicitly distinguishes it from invoice listing, creation, send, void, and delete siblings. An agent can confidently select this tool when retrieving a specific invoice.

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 usage for fetching a single invoice when an id is known, but it doesn't explicitly state when not to use it or mention alternatives like ghl_list_invoices for broader queries. It provides clear context without exclusions, but lacks explicit routing guidance.

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