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

Annotations only declare readOnlyHint=true; the description adds the pagination ceiling ('Max 100 per page') and the composition of each returned record, which is real behavioral context beyond the annotation. It stops short of noting auth requirements, whether filters combine with AND, or ordering.

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, front-loaded with the filter set and followed by return shape and page limit. The trailing 'IntakeQ: GET /invoices' endpoint note is mildly redundant but cheap and confirms the operation type.

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?

With no output schema, the description usefully compensates by describing per-invoice contents, and it covers pagination bounds for an 8-parameter optional-filter tool. Minor gaps: whether filters are conjunctive, default sort order, and behavior on out-of-range pages.

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 100%, with each parameter's format (yyyy-MM-dd, enum statuses, numeric client id) fully documented in the schema. The description merely summarizes the filter dimensions, so it adds little beyond what the schema already carries; baseline 3 applies.

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 ('Query invoices') plus the exact filter dimensions available, so the agent immediately knows this is a list/query operation rather than the single-invoice sibling. It also previews the payload contents ('items, payments and amounts due/paid'), which no sibling shares.

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 filter list implies when to reach for this tool (by client, date range, status, practitioner), but there is no explicit when-to-use or when-not, and no routing to intakeq_get_invoice for a single record. Usage is inferable but not guided.

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