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

Annotations already declare readOnlyHint=true and idempotentHint=true, so safety is covered. The description adds value by noting the output is 'human-readable' and 'decoded', and that transactions are 'recent', which implies a time window. This goes beyond the schema and annotations, giving the agent useful context about output format and recency.

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?

Two sentences with zero filler. The first sentence states purpose, the second provides a concrete example. All content is relevant 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 simple read-only tool with no output schema, the description covers the essential purpose, includes an example, and leverages annotations for safety. It doesn't detail output structure or pagination, but given the tool's simplicity and annotation coverage, it is sufficiently complete.

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%, with each parameter (address, _apiKey, chain) already described. The description does not add semantic depth beyond the schema, though the example call with concrete values reinforces usage. Since the schema carries the burden, baseline 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 returns a decoded transaction history for a wallet, enumerating transaction types (sends, receives, swaps, NFT trades). It distinguishes itself from sibling wallet tools like moralis_wallet_tokens and moralis_wallet_net_worth by focusing on transactions rather than holdings or net worth.

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 for retrieving wallet transaction history but does not explicitly contrast with sibling tools (e.g., 'for token holdings use moralis_wallet_tokens'). The example clarifies invocation but lacks when-not-to-use guidance. Usage is implied rather than explicitly differentiated.

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