Poll Subscription Events

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

The description discloses that the tool does not count against the monthly quota and requires an API key. It explains the polled nature and the content of events (price snapshot and deltas). Annotations already declare readOnlyHint and openWorldHint, but the description adds valuable behavioral context without 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 concise with 6 sentences, each serving a purpose. It is front-loaded with the main action and then provides details. No unnecessary information is included.

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 simple tool with one parameter and no output schema, the description is remarkably complete. It covers usage, authentication, quota impact, polling behavior, and event content. Everything an agent needs to invoke correctly is present.

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 `since` is well described in the schema (100% coverage). The description adds context by explaining it is a cursor from the previous call and that omitting it fetches earliest events. This adds value beyond the schema, justifying a score above baseline 3.

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 clearly states the tool polls for subscription events, using the verb 'poll' and specifying the resource 'subscription events.' It distinguishes itself from siblings like opa_list_subscriptions and opa_get_alert_triggers by focusing on event polling.

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 explains when to use the tool (to catch up on changes since last poll) and how to use it (pass the `since` cursor). It notes that events are polled and must be called periodically. While it doesn't explicitly state when not to use it or name alternatives, the context is clear enough.

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