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

The annotations already indicate read-only, open-world, and non-destructive behavior. The description adds valuable context about how events are decoded (topic0, indexed arguments) and its typical use case in dApp UIs, going beyond the annotation basics without contradicting them.

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 concise, consisting of three short sentences that convey the core functionality, technical detail, and typical usage. No redundancy or unnecessary elaboration.

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 absence of an output schema, the description sufficiently explains what the tool does and its technical underpinnings. It covers the purpose, the event topic mechanism, and a real-world use case, providing enough context for a user to understand its role. It does not describe return format, but that is not required without an output schema.

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 provides comprehensive descriptions for all parameters (coverage 100%). The tool description does not add parameter-specific meaning; it only gives general context about the event decoding process. Baseline of 3 is appropriate.

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 tool's function: retrieving and decoding contract events. It also explains the topic structure, making the purpose precise and distinct from sibling tools like read_transaction or read_block.

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 implies usage by mentioning dApp UI subscriptions and the technical topic mechanism, but it does not explicitly compare to alternatives or state when to prefer this tool over others. However, the distinct purpose and sibling names make the appropriate context clear.

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