update_language

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

With no annotations provided, the description carries full burden for behavioral disclosure. 'Updates language settings' implies a mutation operation, but it doesn't specify required permissions, whether changes are reversible, potential side effects (e.g., affecting user interface), or error conditions. It lacks details on rate limits, authentication needs, or what happens on success/failure, making it inadequate for a mutation tool.

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 extremely concise with just two words, but this brevity comes at the cost of under-specification. While it's front-loaded and wastes no words, it fails to provide necessary context for effective tool use, making it more sparse than appropriately concise. It earns a middle score for structure but lacks substance.

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?

Given this is a mutation tool with no annotations, no output schema, and a minimal description, the contextual information is insufficient. The description doesn't explain what happens after the update (success response, error handling), doesn't mention dependencies or constraints, and provides no behavioral context. For a tool that modifies system settings, this leaves significant gaps in understanding.

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?

The input schema has 100% description coverage, with the single parameter 'displayLanguage' well-documented in the schema as 'The language to display Gmail in, formatted as an RFC 3066 Language Tag'. The description adds no additional parameter information beyond what the schema provides, so it meets the baseline of 3 for high schema coverage without compensating value.

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 'Updates language settings' is a tautology that essentially restates the tool name 'update_language'. It specifies the resource ('language settings') but lacks a clear verb beyond 'updates' and doesn't differentiate from sibling tools like 'get_language' or other update tools. The purpose is vague about what aspect of language settings is being updated.

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 provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing admin permissions), doesn't contrast with 'get_language' for reading settings, and offers no context about appropriate scenarios or exclusions. This leaves the agent with no usage direction.

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