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

With no annotations, the description must carry the behavioral burden, and it does disclose the most important trait: the change is persisted to workspace settings rather than applied per call. It says nothing about permission requirements, whether an invalid mapping_id errors or creates, or reversibility; the return shape is covered by the output schema.

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?

Two tight sentences with the core action front-loaded and the disambiguation second. Minor deductions for the indented multi-line formatting and blank-line artifacts carried over from the source, which add no information.

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 simple two-parameter settings mutation with an output schema, the description covers action, persistence semantics, discovery path and the sibling alternative. The remaining gap is the domain meaning of a mapping and error behavior, which is modest given the tool's simplicity.

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 0%, so the description should compensate. It partially does by pointing to list_language_settings as the source of mapping_id, which is genuinely useful. The formality enum values are self-documenting in the schema, but what a "mapping" actually represents is never explained.

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 with scope: "Change the saved formality for a mapping from list_language_settings." It also differentiates itself from the translate tool's transient formality argument, so an agent can tell the two apart without inspecting either 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?

Explicitly names the alternative (translate's formality argument) and the condition that selects it ("one-off request"), leaving the persistent-settings case for this tool. This is exactly the when-to-use/when-not-to-use framing that routes an agent correctly.

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