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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds real behavioral value: result ordering (newest first), that dates are as Jobber displays them, an invoice-exists flag, and an auth prerequisite (Cotlet API key with app access). Pagination mechanics are left unstated despite the cursor parameter.

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?

Front-loaded with purpose and scope, four compact sentences with no filler. Minor redundancy: 'whether an invoice exists' and 'a flag for jobs that already have an invoice' restate the same fact.

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 carries the return-shape burden and does so by enumerating the fields returned. Auth requirement is disclosed and filters are covered; only pagination behavior and item-count semantics are unaddressed.

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%, so the schema already documents all five parameters. The description reinforces the client and completion-date filters but adds no syntax, format, or default detail beyond what the schema provides, so the 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 (lists jobs) and enumerates the returned fields (client, title, status, dates, invoice flag) plus ordering (newest first), so it is clearly distinguishable from siblings like jobber_list_invoices or jobber_list_clients. It stops short of naming those siblings directly, so an agent must still infer the boundary.

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?

Gives a concrete use case – 'filter by client or by completion date to find work that is done and not yet billed' – which tells the agent when this tool fits. There is no explicit when-not or named alternative, but the context is clear enough to select correctly.

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