Manifest All Shipments by Carrier

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

Goes well beyond the annotations by disclosing the mutation's reach ('closes every shipment that is ready-to-manifest' and creates a single manifest document) and enumerating error states 400/404/409, which matter for a tool with openWorldHint=true that submits to a real carrier. The idempotentHint=true is consistent with the 409 'may already be manifested' note.

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 the core action and organized under bold headers, so it scans well. The 'Returns' section is partly redundant with the existing output schema, and the end-of-day guidance appears twice (prose and the 'Use this tool when' list).

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 two-parameter bulk mutation with an output schema, the description covers when to use it, carrier value handling, side effects, and failure modes — everything an agent needs before invoking it correctly.

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 coverage is 100%, so the baseline is 3; the description adds useful guidance beyond the schema by listing common carrier identifier strings and warning to check StarShipIt account carrier settings for the exact strings. It says nothing about response_format, which is left entirely to 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 with explicit scope: 'Manifest ALL unmanifested shipments for a specific carrier in one operation.' The emphasis on ALL plus 'rather than selecting individually' implicitly distinguishes it from the per-shipment siblings (starshipit_manifest_by_tracking, starshipit_manifest_shipment).

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 clear context — 'at end-of-day or before carrier pickup' — plus a dedicated 'Use this tool when' list. It does not name the specific sibling to use instead when manifesting one shipment at a time, leaving that routing to the agent's inference.

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