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

Annotations only say non-readonly, open-world and non-idempotent; the description goes well beyond that with the one-time signing-secret return, the exact signature header format, the bearer-token auth requirement and the trial-key 403 failure mode. That is exactly the operational context an agent needs before calling a write endpoint.

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?

Front-loaded with the action and trigger, and no sentence is purely filler; the signature-format and auth sentences carry real information. The trailing compliance disclaimer ('not investment advice') is boilerplate and the nested parentheses make it denser than it needs to be.

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?

With no output schema the description correctly explains the return value (signing secret returned once) and covers auth and failure modes. What is missing is behavior on re-registering the same URL or limits per key, small but relevant gaps for a non-idempotent create.

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?

Schema coverage is 67% and the description compensates by explaining the semantics behind both enum values — the 10bp Treasury threshold and the DXY-style index built from ECB reference rates, explicitly not the ICE U.S. Dollar Index. Only the 'description' field's purpose is left untouched, so it falls just short of full coverage.

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?

Opens with a specific verb and resource ('Register an https URL to receive signed JSON alerts') and pins down the exact trigger conditions (10y par yield >10bp, DXY-style index >1%). It never names the sibling endpoints, but the verb 'Register' is unambiguous against list/delete/test_alert_webhook,

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?

States a prerequisite — a Light/Pro/internal key is needed and trial keys get 403 — which tells the agent when the call will succeed. It does not say when to prefer this over alternatives, whether duplicates of an existing URL are allowed, or how to inspect current registrations via list_alert_webhooks.

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