Assign material

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

Annotations already declare readOnly=false, idempotent=true, destructive=false. The description adds context beyond them: repeat calls modify the existing assignment, the operation is reversible with 'One undo step', and it affects cost but not scheduling dates. Permission/authentication requirements are still unstated, which keeps it from a 5.

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?

Four short sentences, front-loaded with the core action and its inverse. Slight overhead in retelling the calculation mode's cost role, but each sentence conveys usable information with no filler.

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 full schema coverage, an output schema, and annotations covering the safety profile, the remaining burden is the behavioral quirks — upsert semantics, undo reversibility, cost-not-schedule effect — all of which are covered. Nothing an agent needs to call this correctly is missing.

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 explains quantity (metric, 0 removes), materialId provenance, and the calculationMode enum in detail. The description only restates the quantity-0 removal, adding no format or constraint detail beyond the schema — the correct baseline of 3 when structured fields do the work.

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?

Names a specific verb and resource ('Assigns material ... to a task') and states the reverse operation (quantity 0 removes). It implicitly distinguishes itself from the sibling assignment tools (task_employee_assignment_set, task_machine_assignment_set) by specifying that the assignee is material from master data.

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 strong selection signal by contrast: material 'carries neither utilization nor capacity: it moves no dates but feeds the cost,' which tells the agent to pick this over date-driving resource assignments. It also notes that calling it again changes the existing assignment (upsert). It does not name the sibling tools explicitly as alternatives, so no exclusions are stated.

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