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

The description merely says 'Update,' which adds no behavioral detail beyond what the annotations already indicate (readOnlyHint=false, idempotentHint=true, destructiveHint=false). It does not disclose whether the update is partial or full, how fields are cleared, or any side effects.

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 a single clear sentence with no filler, making it appropriately concise. However, it is under-specified and lacks any structural elements such as examples or usage notes.

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?

Despite the rich schema, the description does not explain the update semantics (e.g., partial vs full replacement, mutual exclusivity of frequency/cronExpression, how to clear outputSchema) or the response format. With no output schema, the description leaves significant gaps for a tool with such a complex request body.

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 100%, so the schema fully documents parameters, justifying the baseline score of 3. The description itself adds no parameter semantics.

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 states 'Update a signal subscription,' which is a clear verb and resource. However, it does not differentiate among the many sibling subscription tools (create, get, list, trigger, etc.) or other update tools, so it lacks explicit sibling distinction.

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?

There is no guidance on when to use this tool versus alternatives like signal_subscriptions-create, start, stop, or trigger. The description does not mention prerequisites, partial updates, or any usage context.

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