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

Annotations already indicate non-read-only and idempotent behavior. The description adds meaningful context beyond annotations: OAuth persistence requirement, always-on feed with pull methods, phone verification, SMS cap, and type-specific semantics. No contradiction with annotations.

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 front-loaded with the primary action and return value, then moves through auth, types, and delivery. It is dense but every sentence carries useful information; no fluff or repetition. The long run-on structure is a minor organizational weakness.

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?

The description covers core behavior, auth, return id, and delivery options, but its 'Supported types' list omits patent_grant and clinical_trial, and the main description does not mention webhook delivery (schema covers it). Since there is no output schema, the brief return-value note is acceptable but could be richer. These gaps make it incomplete despite strong overall clarity.

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 description goes beyond the schema by providing concrete parameter examples: items:['5.02'] = officer change, topic:'fed', series_id:'UNRATE', and delivery channel examples. Even though schema coverage is 100%, these examples add real-world meaning and constraints (e.g., phone verification, 10/day cap).

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 action: 'Create a proactive monitoring subscription to a live-data event stream' and states the return value ('Returns the new subscription id'). This clearly distinguishes subscribe from sibling tools like list_subscriptions 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?

It provides clear usage context: requires a Pipeworx OAuth account, lists supported subscription types with concrete examples, and explains delivery channels including the always-on feed and optional email/SMS. It does not explicitly call out when to use alternatives, but the context is specific enough for tool selection.

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