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

Annotations already declare readOnlyHint=false, destructiveHint=true and idempotentHint=true. The description adds real context beyond them: the change is user-visible in two places (the connected-agents list and reminder tags) and is limited to the caller's own key. It does not explain that the change is trivially reversible by renaming again, which would soften the destructiveHint a caller sees.

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?

Front-loaded with the action and scope, then usage conditions, then an example. Every clause is informative; the parenthetical explaining where the name appears is worth its length. Minor awkwardness: the first sentence is split across a line break mid-clause.

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 one-parameter mutation with no output schema but full annotations, the description covers scope, visibility of the effect, and when to invoke it. Missing only an indication of what happens on success or on invalid input (e.g., an empty name), which is a small residual gap.

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% and the single 'name' parameter is documented there, so baseline is 3. The description earns above baseline by supplying a naming convention and example ('Claude Code on Alex's MacBook'), which tells the agent what a good value looks like beyond the 60-character constraint.

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 ('Rename yourself: change the name of the key you are connected with') and pins the scope with 'Only your own key is renamed.' None of the alarm siblings perform renaming, so the agent can distinguish it immediately.

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?

Gives clear trigger conditions: 'Use it when the user asks, or when the name no longer says what you are and where you run,' with a concrete example name. It does not name an alternative tool or a when-not case, but no sibling overlaps this function, so the guidance is effectively complete.

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