subscribe_price_updates

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

With no annotations at all, the description carries the full burden and leaves key traits unstated: whether subscribing creates persistent server-side state, how updates are delivered (push vs. polling), whether the subscription is tied to a session or account, and how it is torn down. Only 'real-time' hints at behavior, which is thin for a stateful subscription operation.

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?

One short sentence, front-loaded with the verb and resource, with no filler. Nothing is wasted.

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 stateful subscribe operation with no annotations and no output schema, the description should say what the caller receives and how the subscription is managed or cancelled. Those essentials are missing, leaving an agent unable to predict the result of a successful 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?

There is a single parameter with 100% schema description coverage and a documented default of USD, so the schema already does the work. The description's phrase 'in a specified currency' adds nothing beyond the schema, so baseline 3 is appropriate.

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 (subscribe) and resource (real-time Bitcoin price updates) with a currency scope. It is distinguishable from the sibling get_realtime_price by the word 'subscribe', but it never names that sibling to make the distinction explicit.

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?

The description gives no guidance on when to use this instead of a one-shot read like get_realtime_price, nor any mention of prerequisites. It also omits the natural follow-up path for a subscription tool, such as cancel_subscription or list_subscriptions, which are present as siblings.

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