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

Beyond annotations (destructive, idempotent, open-world), the description discloses important behavior: omitted fields remain unchanged, dependent recipe costs are affected, subrecipe ingredients are excluded, and it is a PUT to /ingredient_costs/{id}. This adds useful context about side effects and restrictions, though auth/rate-limit details are not covered.

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?

The description is front-loaded with 'WRITE', compactly lists the affected fields, and packs side effects, exclusion, and endpoint into a few dense lines. Every clause adds operational meaning without repetition.

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 destructive mutation tool with annotations covering safety traits and 100% schema coverage, the description supplies the missing operational context: partial update, cascading recipe-cost impact, subrecipe exclusion, and HTTP method/path. Nothing an agent needs to call it correctly appears absent.

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 baseline is 3; the description adds value by clarifying that any omitted fields stay unchanged, which is partial-update semantics not stated in the schema. It also maps 'date' to the effective_at parameter and lists the mutable fields in plain language.

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 description states a specific verb and resource: 'change an existing ingredient cost entry', lists the mutable fields, and notes partial-update behavior. It distinguishes itself from creation by emphasizing 'existing', but does not name the sibling create_ingredient_cost or get_ingredient_cost explicitly.

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?

It provides a clear usage context ('change an existing ingredient cost entry') and one explicit exclusion ('Not allowed for subrecipe ingredients'). However, it does not name alternative tools such as create_ingredient_cost or list_ingredient_costs, so an agent must infer when to choose this over siblings.

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