tailscale_update_key

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

Annotations already indicate readOnlyHint=false, idempotentHint=true, destructiveHint=false. The description adds behavioral details: supported fields per key type, rejection of unsupported fields for auth keys. No contradictions.

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?

Single concise paragraph, front-loaded with main action, every sentence adds distinct value – no 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?

Given 8 parameters (some nested) and no output schema, the description covers key-type-specific behavior and parameter usage rules thoroughly. Could mention error behavior (e.g., key not found), but overall complete.

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 baseline is 3. The description adds significant value by mapping fields to key types and explaining acceptance rules beyond the schema definitions.

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 clearly states 'Update an existing key', specifies supported fields per key type, and distinguishes from siblings like tailscale_create_key and tailscale_delete_key by outlining key-type-specific constraints.

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 clear context on which key types accept which fields, guiding correct invocation. However, it does not explicitly state when to use this tool versus alternatives (e.g., create or delete), though the context strongly implies it.

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