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

The description adds meaningful behavioral context beyond the annotations, explaining that the webhook is edge-triggered (fires once on crossing) and checked hourly, and that it returns a subscriptionId for later management. This goes beyond the basic read-only/idempotent/destructive hints and provides useful operational detail.

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 only four sentences: purpose, supported signals, trigger behavior, and use cases. It is well-structured, front-loaded with the main action, and every sentence provides useful information without redundancy.

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 webhook subscription tool, the description covers purpose, trigger behavior, supported signals, return value, and use cases. The output schema presumably handles return structure details. It lacks some advanced details like webhook authentication or retry behavior, but these are not essential for tool selection and 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 input schema already provides full descriptions for all 5 parameters (100% coverage), so the baseline is 3. The description reinforces the threshold score range and signal types but does not add significant new meaning beyond what the schema already states.

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 uses a specific verb ('Register') with a clear resource (webhook) and scope (DPX intelligence signal crossing a threshold). It also lists supported signals, which distinguishes it from sibling subscription management tools like intelligence.subscription.get and intelligence.subscription.delete.

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 explicitly names relevant use cases ('treasury alert systems, TMS integrations, or autonomous agent monitoring loops'), providing clear context for when to use the tool. However, it does not explicitly contrast with alternatives or state when not to use it, so it falls short of a 5.

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