get_invoice

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

No annotations are provided, so the description carries full burden. The description states it returns line items and mentions [tier: readonly-owner] which hints at access level/auth requirements. However, it doesn't disclose behaviors like error cases for invalid IDs, response shape, or pagination (if any for line items). The tier note adds modest value but doesn't fully compensate for missing 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 description is compact at two sentences, front-loads the core purpose, and adds the API mapping and tier note. It's efficient without being under-specified. The '[tier: readonly-owner]' addition is useful context in a single concise token.

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 single-resource GET with one parameter, the description is reasonably complete: it states what it returns (full details plus line items) and the API mapping. However, with no output schema, no annotations, and no description of what 'full details' contains (fields like payment status, due date, totals), an agent has limited insight into the tool's output richness or error behavior.

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 only 1 parameter and 0% schema description coverage, the description doesn't elaborate on invoice_id beyond what the schema provides. The schema alone defines it as a required string, and the description doesn't add format expectations (e.g., UUID style, numeric ID). However, with only a single self-explanatory parameter, the gap is minimal — the schema and tool name convey sufficient meaning.

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 'Get full details for a single invoice, including line items' with a specific verb (get), resource (invoice), and scope (full details including line items). It maps to GET /invoices/{id} and distinguishes from siblings like list_invoices (listing vs single) and list_job_invoices (which scopes by job).

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 ('get a single invoice') and the sibling set includes list_invoices for listing, which provides natural differentiation. However, there's no explicit statement of when to use this vs alternatives like list_invoices, get_estimate, or get_job. The [tier: readonly-owner] note provides some access context but no explicit when/when-not guidance.

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