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

With no annotations, the description carries the full burden. It discloses the side effect ('disassociate webhook delivery'), the return value ('deleted confirmation'), and the cost (10 tokens). It does not explicitly state irreversibility or permission requirements, but delete semantics and side effects are communicated. This exceeds the minimum.

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, each purposeful: purpose first, then usage, then return/cost. No wasteful words. The cost is included, which is useful operational trivia. Highly concise and front-loaded.

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 destructive tool with one optional parameter and an output schema, the description covers purpose, prerequisite, parameter behavior, return type, and cost. It could more explicitly mention irreversibility or consequences of disassociating webhook delivery, but the given context is sufficient for an agent to use it correctly.

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 baseline is 3. The description repeats the schema's parameter guidance ('Pass clerk_instance_id to target a specific connection, or omit it to use the default account') and adds the prerequisite call. This is helpful but does not significantly go beyond the schema's own description.

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 clearly states the action: 'Delete the Svix app associated with a connected Clerk application and disassociate webhook delivery.' This uses a specific verb and resource, and it distinguishes the tool from siblings like create_svix_app and create_svix_dashboard_url.

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?

It provides explicit prerequisite guidance: 'Call clerk.get_connected_accounts first.' It also explains how to target a specific connection vs. the default account. It does not explicitly name alternatives or exclusions, but the context is clear and actionable.

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