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

Annotations only declare readOnlyHint=false, destructiveHint=false, openWorldHint=false; the description adds far more than that – the company-wide blast radius, named per-extension side effects (WooCommerce sync, TIMEmSYSTEM defaults, Stripe billing), the money implication of a non-zero `price`, and the fact that installation alone does not complete setup. This is exactly the behavioral context annotations cannot carry.

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?

Dense but well ordered: action and ID sourcing first, then the confirmation requirement, then side effects, money, and post-install caveats, ending with refusals. The length is justified by the high-stakes mutation, though a couple of clauses could be trimmed without loss.

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 one-parameter mutation with no output schema, the description covers everything the agent needs: prerequisites, blast radius, monetary consequences, follow-up obligations, and failure modes. Nothing material about calling it correctly is left implicit.

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's schema description already says 'extensionId from get_extension_catalog — not a name, not a guid'. The description restates this constraint rather than adding new syntax or format detail, so it meets the baseline without exceeding it.

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 with explicit company-wide scope ('Install an extension for the whole company'), which cleanly separates it from the sibling flow_install_extension. It also pins the required input ('Takes the `extensionId` from get_extension_catalog, never a name'), so the agent knows exactly what this does before opening the 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 a hard precondition (CONFIRM WITH THE MERCHANT BEFORE CALLING, naming the extension), the sourcing rule for the ID, and explicit refusal conditions (plan excludes the extension, caller lacks the Extensions permission, already installed). The 'installing twice is not a no-op' note further clarifies the when-not boundary.

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