ms_set_key

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

Beyond annotations (idempotentHint=true, destructiveHint=false), description reveals key validation, local save with secure permissions, no echo, and chat transcript exposure risk. No contradiction with annotations.

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?

Well-structured with front-loaded purpose, warning, args list, and post-condition, but slightly verbose. Could trim alternative mention, though useful.

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?

Complete for tool complexity: includes purpose, arguments, prerequisites (boolean flag), behavior, and success outcome. Output schema exists so return details not needed.

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?

Despite 0% schema coverage, the description provides detailed parameter meanings: credentials dict, cabinet selection logic with defaults, and the required boolean guard. Fully compensates for lack of schema descriptions.

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 explicitly states 'Change / rotate the API key from chat' with a specific verb and resource. It clearly distinguishes from alternative (installer) and implies use cases like expired or leaked key.

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?

Provides explicit when-to-use (key expired/leaked) and when-not-to-use (prefer installer to avoid key in chat). Also advises using scoped keys and rotation, guiding agent on best practices.

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