update_rejections_out

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

Annotations already flag destructiveHint=true, and the description adds the crucial specificity of WHAT is destroyed: 'replacing its item lines and narration' — meaning existing lines are not merged but overwritten. The matching/collision caveat reference further flags non-obvious behavior, though the details are deferred rather than disclosed. No contradiction with annotations; idempotentHint=true is consistent with a replace-to-state operation.

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 sentences, zero filler: purpose is front-loaded first, field deltas second, caveat routing third. The 'Same fields as... plus...' and 'Same caveats as...' constructions compactly inherit documentation from sibling tools without repeating it. Every sentence earns its place.

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 4-parameter, fully schema-covered update tool with annotations covering the destructive/idempotent profile, the description is largely sufficient. The main gap is that the matching/collision caveats are only referenced via update_material_in, so an agent lacking access to that sibling's description would miss critical behavior; return/response shape is also unaddressed, though there is no output schema to anchor it.

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 all four parameters (date, items, narration, voucherNumber) are already documented in the schema. The description adds modest value by clarifying that voucherNumber is the update key ('plus voucherNumber') and echoing the replace semantics that the schema's items description also states. This is the baseline-3 case where schema does the heavy lifting.

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 opening sentence states a specific verb, resource, and scope: 'Update an existing Rejections Out voucher in TallyPrime, replacing its item lines and narration.' It explicitly differentiates from the create twin by noting 'Same fields as create_rejections_out, plus voucherNumber,' so an agent can tell update from create without opening the schema.

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 qualifier 'existing' clearly implies this is for already-created vouchers, and the reference to create_rejections_out as the field baseline names the natural alternative. The pointer 'Same matching/collision caveats as update_material_in' routes the agent to relevant caveats, though it defers the actual exclusion conditions (e.g., what happens on mismatch) instead of stating them.

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