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

The description adds that results are scoped to the caller and lists the exact fields returned (id, type, params, created_at, last_fired_at, fire_count). Annotations already declare readOnlyHint and destructiveHint false, so this supplements rather than repeats. No contradiction.

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 three short sentences: action, return fields, and usage guidance. Each sentence adds value with no redundancy.

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 read-only tool with rich annotations, the description covers what, what returns, and when to use it. The output fields are enumerated, and no additional context seems necessary.

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 only parameter include_inactive is fully described in the schema (100% coverage). The description does not mention the parameter, so it adds no extra semantic value beyond the baseline.

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 'List the caller's active subscriptions' with a specific verb and resource. It also enumerates the return fields, making it clearly a read/list operation distinct from sibling tools like subscribe and unsubscribe.

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?

Says 'Use this to review what you're monitoring before adding more or to find an id to cancel,' giving clear use cases. It doesn't explicitly name alternatives, but the context implies when this is appropriate (before mutations or cancellation).

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