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

The description presents a read operation ('Fetch', GET endpoint), yet annotations declare readOnlyHint=false and idempotentHint=false, which implies possible state change and non-repeatable behavior not explained anywhere. The added cost note ('see your plan — endpoint not in the public credit manifest') is genuinely useful behavioral context beyond the annotations, but the read/write mismatch undermines trust.

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 opening sentence is front-loaded and every bracketed metadata line (group, endpoint, required, cost) is compact and earns its place. Slightly mechanical, but no wasted prose.

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?

An output schema exists, so return values need not be described, and the ownership scope is stated. However, the definition leaves the read-only-versus-mutating question unresolved despite the contradictory annotation, and gives no error/auth context for a 3-parameter tool.

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%, so the schema itself already documents id, fields, and precision in detail, making 3 the baseline. The description only repeats '[Required: id]' and adds no format or syntax meaning beyond what the schema provides.

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?

States a specific verb and resource ('Fetch a single webhook subscription') plus an ownership scope ('owned by the authenticated user'), which distinguishes it from the sibling list tool astroway_webhooks_webhooks and from astroway_webhooks_subscribe. It stops short of naming those alternatives explicitly.

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?

There is no when-to-use or when-not-to-use guidance; the definition never says to prefer this over the listing endpoint or the subscribe/test siblings. The '[Required: id]' note only restates schema requirements rather than indicating when the call is appropriate.

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