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

With no annotations, the description carries the full behavioral burden, and it does contribute one genuinely non-obvious fact: delivery resumes from the checkpoint so no events are skipped, which tells the agent this is a resumable state change rather than a reset. It omits other material behaviors — required permissions, whether the call is idempotent on an already-enabled subscription, error modes for an invalid or deleted id, and what the response looks like.

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?

Two short sentences, zero filler, with the core action stated first and the resumption caveat second. Nothing could be removed without losing information.

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?

This is a low-complexity single-parameter tool with no output schema, so the description need not explain return values. However, with no annotations and a completely undocumented parameter, the definition still leaves an agent guessing at the id's meaning and at the failure/idempotency semantics of the call.

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 0% and the schema only declares an untyped-by-name "id" string, so the description is the only place the parameter could be explained — but it never mentions the id at all. It does not say whether this is the subscription id, a source id, or a user id, nor the accepted format, leaving the sole parameter essentially undocumented.

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?

"Turn a disabled subscription back on" gives a specific verb and a specific resource state transition, so an agent knows exactly what the tool does. It does not name create_subscription or delete_subscription as alternatives, but the enable/disable framing is unambiguous on its own.

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?

Use is implied by the precondition "a disabled subscription" — an agent can infer it should only call this on a subscription that is currently off. There is no explicit when-not guidance (e.g., what to do when the subscription is already enabled) and no routing to create_subscription for subscriptions that don't exist yet.

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