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

The description discloses important behavioral traits beyond the annotations: authentication requirements, the fact that subscriptions cannot persist for anonymous/BYO accounts, return of a subscription id, and constraints like SMS phone verification and a 10/day cap. It does not contradict the annotations (readOnlyHint false, idempotentHint true).

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 relatively long but front-loaded with the core action and return value, then organized by supported types and delivery channels. Each sentence adds useful information, but the dense prose could be more readable with better formatting. It remains appropriately sized for the complexity.

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?

Given the tool's complexity and the rich schema, the description covers the critical aspects: purpose, required auth, main subscription types, delivery channels, and constraints. It omits two enum types (patent_grant, clinical_trial) and webhook delivery in the description, but the schema fully covers those, so the overall picture is complete enough for correct invocation.

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 schema already provides 100% parameter coverage with detailed descriptions for each parameter, including type-specific filters and delivery channel properties. The tool description adds some examples like items:["5.02"] and topic:"fed" but these largely overlap with the schema. It does not substantially enhance parameter understanding beyond what the schema offers.

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 identifies the tool as creating a proactive monitoring subscription to a live-data event stream, with a specific verb ('Create') and resource. It also differentiates from siblings like list_subscriptions and unsubscribe by focusing on the creation action, and notes the return value (subscription id).

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 usage context: it requires a Pipeworx OAuth account, is not available for anonymous/BYO users, and gives delivery channel options including the always-on feed and optional email/SMS. It does not explicitly exclude alternatives or state when not to use it, but the context makes it clear enough for an agent to select appropriately among siblings.

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