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

Annotations already cover readOnly, idempotent and non-destructive, so the bar is lower; the description still adds real value by disclosing the permission requirement and the security guarantee that signing secrets are never returned. It stops short of describing result shape (e.g., which fields a subscription carries) or paging behavior.

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?

Three short sentences, purpose first, then permission, then the two caveats. Nothing is repeated and no sentence is filler.

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 single-parameter read with full schema coverage and read-only annotations, the description covers scope, auth and the key security caveat. With no output schema, a brief note on what a listed subscription contains (URL, events, active state) would have closed the remaining gap.

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 100% and the single parameter already documents the 24-hex ObjectId format and the 'never a personal platformId' constraint. The description only reinforces the workspace scoping ('one Workspace's') without adding format or sourcing detail beyond the schema.

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 gives a specific verb and resource ('List ... signed publishing webhook subscriptions') and scopes it to a single Workspace, which separates it from the create/update/delete/regenerate webhook siblings. It does not explicitly name the sibling that handles personal subscriptions, only noting they are 'separate', so routing is implied rather than stated.

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?

'Requires Workspace settings permission' is a concrete prerequisite an agent must check before calling, and 'personal subscriptions are separate' steers away from an out-of-scope use. There is no explicit when-not guidance or named alternative tool for the personal case.

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