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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds real value beyond that: it explains the read is scoped to the pack catalog plus a single activation preference per pack, and that it 'measures nothing on its own' — pre-empting a mistaken expectation of computed figures. No return format is described, but an output schema exists.

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 verb and resource, then the definition, then the sibling pointer, then a scope caveat. Every sentence carries distinct information and nothing is repeated from annotations or schema.

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 the description needn't explain return values, and the annotations cover safety. The description supplies the concept definition and the read-only/measurement caveat, which is enough for correct invocation. It could say slightly more about the workspace-scoping behavior implied by workspace_id/workspace_scope, but the schema handles that.

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 all three parameters (workspace_id, conversation_id, workspace_scope) are already documented in detail in the schema. The description mentions no parameter at all — not even that workspace scoping applies — so it adds nothing over the structured field docs and lands on the baseline of 3.

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 ('List the packs Well offers') and then defines the domain concept ('a pack is one shared preset — a few columns on an existing table — a workspace switches on in one click'). It also enumerates the returned fields (id, name, description, columns, active), which no sibling tool offers, so an agent can distinguish it from the many list_* tools.

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?

Explicitly routes the mutation case to a named sibling: 'Use `well_update_pack` to switch one on or off.' That is a clear read-vs-write split. It doesn't say when to skip this tool (e.g. when the agent already knows activation state), so it stops short of full when/when-not guidance.

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