Create Cost Code

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

Annotations already indicate non-read-only, non-idempotent, and non-destructive behavior. The description adds meaningful context: returns HTTP 201 with new id, explicitly states repeated calls create new records, and discloses common error statuses (401, 403, 404). This goes beyond the annotations without contradicting them.

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 compact, front-loaded with the core purpose, and every sentence adds value (return behavior, error handling, required params, API context, endpoint). No redundancy or fluff.

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 3-parameter creation tool with no output schema, the description covers the essential aspects: HTTP 201 response with id, non-idempotence, error payloads, required parameters, API category, and endpoint. It could be more complete by explaining what the cost_code object should contain, but the schema already labels it as a 'cost Code object'.

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% with descriptive property texts, so the baseline is 3. The description reinforces that project_id and cost_code are required but provides no additional detail about the cost_code object's structure or accepted fields, which would have added value given the schema's open additionalProperties.

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 uses a specific verb and resource ('Create a new Cost Code') and clearly distinguishes from sibling tools by stating 'calling it again creates another record,' which establishes non-idempotent creation versus update/sync tools.

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 clear context on when to use this tool (to create a new cost code) and warns against accidental duplicates ('calling it again creates another record'). It lists required parameters and common failure statuses, but does not explicitly name alternatives like update_cost_code or explain when not to use it.

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