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

The description discloses that it returns null if the transaction is not found, which is important behavioral information. Since no annotations are present, the description carries the full burden and handles it adequately for a read-only operation.

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, clear sentence that front-loads the verb and resource. There is no wasted content.

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 lookup tool with one parameter and no output schema, the description covers the core functionality and an important edge case (returning null). It is complete for its complexity level.

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 coverage is 100% and the schema already describes the parameter well ('0x-prefixed, 32 bytes'). The description adds minimal extra meaning beyond 'by hash', so it meets the baseline but does not improve it.

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 action (fetches) and the resource (transaction by hash). It distinguishes from siblings like fuse_get_balance or fuse_get_receipt, which serve different purposes.

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 when needing transaction details by hash, and distinguishes from other tools by the specific resource. However, it does not explicitly mention when not to use it or provide alternative tool names for similar queries.

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