Retrieve and filter bills by status or vendor ID to locate specific invoices for accounts payable review or processing.
List bills, optionally filtered by status and vendor.
| Name | Required | Description | Default |
|---|---|---|---|
| status | No | received, matched, exception, approved or release_requested | |
| vendor_id | No | Vendor id, e.g. V-01 |
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are supplied, so the description carries the full behavioral burden. "List" weakly implies a read-only operation, but nothing is said about ordering, pagination, result limits, or scope — significant gaps for a search tool with zero annotation coverage.
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?
A single tight sentence with the resource and filters front-loaded and no wasted words. It is minimal but functional rather than padded or rambling.
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?
An output schema exists, so return values need not be explained, and complexity is low with two optional parameters. Still, with no annotations and no guidance on result ordering or how it relates to get_bill, the definition is only adequate rather than 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 100%, so both parameters are already documented with their valid values, establishing a baseline of 3. The description only restates the filter fields (status, vendor) without adding format or matching semantics beyond the schema.
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 ("List bills") plus the two filter dimensions, which distinguishes it from the singular sibling get_bill. It does not, however, explicitly name get_bill as the alternative for single-record lookups.
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?
"Optionally filtered by status and vendor" implies the filtering use case but gives no explicit when-to-use vs get_bill or when-not-to-use guidance. Usage is inferable from the name and description rather than stated.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.