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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so the safety profile is covered structurally. The description adds real value beyond that — the body comes back as a JSON string plus a checksum, and the string is meant to be parsed and resubmitted — but it says nothing about size limits, error behavior for a nonexistent version, or whether historical versions are immutable.

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 sentences, front-loaded with the action, then the return shape, then the sibling disambiguation. Every clause carries information an agent needs; nothing is repeated from the annotations.

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 an output schema present, return values need not be explained, and the rich annotations cover safety and idempotency. The description fills the remaining gaps that structure cannot: the JSON-string encoding of the body, the checksum, the default-version behavior, and the read-vs-edit split against get_app.

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 slug/app_id/version are already documented, and the description only restates the "omit version for latest" default. It earns slightly above baseline by framing why you would fetch a specific version at all — to diff or edit and resubmit — which the schema does not convey.

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 ("Read back the full stored definition of an app version by slug or id") and immediately names what it is not: "This is the EDITING view; get_app returns the typed published manifest for reading." An agent can distinguish this from get_app and list_app_versions without opening any schema.

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?

Gives the explicit selection rule against the nearest sibling — use this for editing, get_app for reading the typed published manifest — and states the default behavior ("Omit version to get the latest version"). The intended downstream workflow (diff, edit, resubmit as a new version) is spelled out rather than implied.

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