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

Beyond the read-only hint, the description discloses deep behavioral traits, listing specific checks (sighash types, taproot/witness scripts, fee risks). Crucially, it includes a vital security warning ('Never send private keys'), which is non-trivial behavioral context.

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 dense with information but highly efficient. It front-loads the core technical functionality and uses a concise structure to deliver both the technical scope and the necessary security warning.

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 complexity of Bitcoin PSBT and the associated parameters, the description is remarkably complete. It covers the data input, the specific validation steps performed (fee, change, scripts), and the safety protocols the user must follow.

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?

Although schema coverage is 100%, the description adds high-value semantic information by specifying the accepted input formats (base64 or hex). It also frames the optional payment-related parameters within the context of the inspection's risk analysis.

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 uses a specific verb ('Inspect') applied to a complex resource (Bitcoin PSBT, BIP174). It clearly distinguishes its function by emphasizing the goal: verifying data and flagging risks before the signing process.

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 tool explicitly states its use case is inspection 'before signing,' providing a clear operational context for when to use it. While it doesn't explicitly list alternatives, its specific technical functions (fee checks, script analysis) inherently define its purpose better than simpler tools like 'check_bitcoin_address'.

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