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

Beyond the annotations (readOnlyHint=false, idempotentHint=true), the description discloses important behavioral traits: authentication requirements (OAuth, anonymous/BYO cannot persist), SMS verification and daily cap, webhook auto-disabling after 10 consecutive failures, and that the webhook signing secret is returned only once. These details add substantial value.

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 dense and front-loaded, leading with the core purpose and return value. However, it repeats some details already present in the schema (e.g., SMS verification, webhook signing) and could benefit from bulleted lists for clarity. Overall it is efficient but slightly redundant with the schema.

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 absence of an output schema, the description explains the return value (new subscription id, webhook secret shown once) and covers all subscription types, parameter structures, delivery options, prerequisites, and failure behaviors. It is fully complete for a complex creation tool with nested objects.

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?

Although the schema already has 100% coverage, the description enriches each parameter with concrete examples and domain context: sec_8k items codes mapping to officer changes, polymarket_edge topics like 'fed', fred_series with series_id, and clinical_trial requirements such as 'sponsor or condition required'. The delivery parameter is also explained with webhook HMAC signing details and email/SMS specifics, going well beyond the schema's property descriptions.

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 opens with a specific verb and resource: 'Create a proactive monitoring subscription to a live-data event stream.' It clearly states the return value (new subscription id) and distinguishes itself from sibling tools like list_subscriptions, recent_alerts, and unsubscribe by focusing on creation and monitoring.

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 provides clear context on when to use the tool (to establish ongoing monitoring) and includes prerequisites (Pipeworx OAuth account, phone verification for SMS). It also implicitly contrasts with pulling via the always-on feed by noting 'pull via recent_alerts or GET registry.pipeworx.io/alerts.json', but does not explicitly state exclusions or alternatives such as 'for one-time query, use X'. Thus it has clear context but lacks explicit when-not guidance.

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