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

With no annotations provided, the description carries the full burden of behavioral disclosure. It explicitly states the side effect of creating both a destination and a routing rule in one call, and implies persistence with 'standing forwarding.' It does not disclose potential idempotency, validation, or error behaviors, but the key side effect is clearly communicated, exceeding the baseline.

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?

The description is two sentences, front-loaded with the core purpose, followed by concise usage guidance. No redundant or filler content. Every sentence contributes meaning, and the structure is easy to scan.

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?

Given the tool's complexity (6 parameters, nested condition_tree, multiple resources created) and lack of output schema, the description covers the core semantics and the most important usage scenarios. It does not explain return values or prerequisites (e.g., bucket must exist), which would be helpful, but the essential context for invoking the tool is present.

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?

The input schema already covers all 6 parameters with descriptions (100% coverage). The description adds value by explaining the relationship between forward_all and condition_tree as mutually exclusive alternatives, and by referencing the condition_tree grammar as the same as the routing engine. This goes beyond the schema's static parameter descriptions.

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 explicitly states the action: 'Set up standing forwarding from a bucket to a URL.' This is a specific verb with a clear resource and destination. It distinguishes from sibling tools because none other mention forwarding, and it adds detail that it creates the destination and routing rule in one call.

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?

The description provides clear guidance on parameter choice: use forward_all:true for all events, or condition_tree for matching events. It also references the routing engine's AND/OR grammar, which gives context. No explicit sibling alternatives are named, but the tool's unique purpose within the sibling set makes this less critical. It lacks exclusions or when-not-to-use scenarios, so not a 5.

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