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

The annotation declares destructiveHint=true, while the description describes the operation as an 'additive configuration', which frames it as non-destructive and creates a direct tension with the annotation an agent could act on. Credit is partial because the description does disclose the management endpoint and the required/optional parameter split, but the conflict over the write's safety profile is a real gap.

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 short sentences, front-loaded with the core action, followed by the endpoint and the required/optional split. Nothing is padded, though the endpoint path duplicates what a caller rarely needs at selection time.

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 7-parameter creation tool with nested objects and no output schema, the description covers what it creates and which inputs are mandatory, but says nothing about what is returned (e.g. a created agent id) or any auth/quota constraints. No output schema exists, so return-value information had to come from the description and is 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 all seven parameters are already documented in the schema. The description's 'Requires model and name; instructions, tools, completion_args, description and handoffs are optional' restates the required/optional split without adding syntax, format, or constraint detail beyond what the schema provides.

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 ('Creates a Mistral Agent') plus the underlying endpoint (POST /v1/agents), and the parenthetical '(additive configuration)' hints at the scope of the change. It does not name a sibling tool to differentiate from, but the create verb is naturally distinct from the get_/list_ siblings.

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 description tells the agent what is required (model, name) versus optional, which implies when the tool can be called, but it never states when to create a new agent versus reuse/get an existing one, nor any prerequisites. Usage is implied rather than guided.

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