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

Annotations already declare destructiveHint=true and idempotentHint=false, but the description adds real context beyond them: the deletion is permanent/irreversible and it cascades to the run's insights, and the operation is confined to the authenticated customer's scope. It does not mention the required confirm flag (left to the schema) or any auth/rate-limit nuance, so it is strong rather than exhaustive.

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 terse sentences, front-loaded with the destructive action and its cascade, then the irreversibility warning, then the scope constraint. Nothing is padded and the most important fact (permanent, irreversible) appears immediately.

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 three-parameter destructive tool with no output schema and annotations that already flag destructiveness, the description covers the essentials an agent needs: permanence, cascade to insights, and customer scoping. Only a note about the confirm prerequisite or irrecoverability mechanics would fully round it out.

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 conversationId, customerId, and confirm are all documented in the schema; the description adds no syntax or format detail for any of them. Baseline 3 applies when the schema carries the parameter burden, which is the case here.

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 ('Permanently delete a run') and even names the cascading side effect ('and its insights'), which cleanly separates it from the other delete_* siblings that target agents, optimizations, users, and webhooks. It stops short of explicitly contrasting with any sibling or an alternative action, so it lands just below the top mark.

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?

There is no when-to-use guidance, no prerequisites, and no mention of alternatives (e.g. archive, or how it differs from other removal tools). The scope note 'Scoped to the authenticated customer' describes reach rather than when to invoke the tool, leaving usage entirely to inference.

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