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

The description provides useful context about the output content (snapshots, position changes, direction indicators) but discloses no behavioral traits such as read-only nature, rate limits, or data granularity. With no annotations provided, the description carries the full burden and partially meets it by indicating the historical/read-oriented nature, but lacks deeper transparency.

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 a single concise sentence that immediately conveys the core functionality and adds relevant detail about snapshots, position changes, and direction indicators. Every word earns its place, and the structure is clean.

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 tool with a complete parameter schema, the description offers a basic understanding of the output. However, without an output schema or annotations, it lacks details on response format, error scenarios, and how it differs from similar tools like portfolio_history, making it only minimally 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?

The input schema already has 100% coverage with descriptions for both parameters (address and lookback). The description does not add any parameter-specific meaning beyond what the schema provides, so the baseline of 3 applies.

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 what the tool does: shows wallet portfolio over time with snapshots, position changes, and direction indicators. The verb is implied ('get history'), and the resource is specific. However, it does not distinguish from the sibling tool 'portfolio_history', which likely serves a similar purpose, so it misses the differentiation needed for a 5.

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?

No guidance is given on when to use this tool versus alternatives. The description is purely declarative and does not mention exclusions, alternatives, or specific use cases. With many sibling tools like portfolio_history and wallet_graph, the lack of any usage direction leaves the agent to guess.

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