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

With no annotations, the description carries the full burden, and it does disclose two valuable traits: callbacks are signed, and the signing secret is returned only once (so it must be captured immediately). It omits auth/permission requirements, whether re-calling overwrites the existing endpoint, retry/failure behavior, and delivery semantics — meaningful omissions for a mutation tool with zero annotation coverage.

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?

Two compact sentences, front-loaded with the core effect and the polling alternative, then the one-time secret warning. The event list is long but each entry is necessary information, not padding.

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?

There is no output schema, and the description does cover the key return value (signing secret, returned once). However, for a write/configuration tool with no annotations and no output schema, an agent still cannot tell what happens on repeated calls, what the response body looks like beyond the secret, or what permissions are needed.

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 description coverage is 100% and there is a single parameter ('Your https endpoint'), so the schema already explains the input. The description adds only the implicit HTTPS requirement, which the schema also states, so baseline 3 applies.

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 names the concrete effect (signed HTTPS callbacks on quest status changes) and enumerates every event type, which makes it easy to distinguish from read tools like get_quest. The registration action itself ('set_webhook') is only implied by 'receive' and 'returns a signing secret once', so the agent must infer that calling this registers an endpoint rather than fetching callbacks.

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 gives an explicit alternative and the condition that selects it: use this 'instead of polling get_quest'. It does not state when not to use it, whether only one webhook can exist, or whether a second call replaces the first, which leaves real gaps for a configuration tool.

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