prepare_btc_lifi_swap

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

The description provides extensive behavioral details beyond annotations: source-side scope (segwit/taproot only), that LiFi auctions routes, the PSBT contains specific outputs (vault deposit, OP_RETURN, change, fee), Ledger app clearsigns (no blind sign), verification block contents, and server-side checks. This fully informs the agent of the tool's behavior and constraints.

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 well-structured with paragraphs covering purpose, process, and verification. It is front-loaded with the most essential information. While lengthy, every sentence adds value. Minor improvement could be tightening some phrasing, but overall it is concise given the complexity.

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?

Despite no output schema, the description fully explains the return value (PSBT with 15-min handle) and the verification block details. It covers all necessary aspects: dependencies (LiFi, Ledger), constraints (source address type, destination chains), and failure conditions (TRON rejection). The agent has enough information to use the tool correctly.

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 has 100% description coverage, with each parameter clearly documented. The tool description adds overarching context such as 'multi-source consolidation is out of scope' and explains why 'max' is not supported for amount. While per-parameter details are already in schema, the description enhances understanding of how parameters interact in the broader workflow.

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 verb 'build' and the resource 'unsigned Bitcoin PSBT-v0' with the specific purpose of bridging native BTC to a token on another chain via LiFi's aggregator. It distinguishes itself from sibling tools like prepare_btc_send by emphasizing the cross-chain bridge aspect and explicitly listing supported destinations while rejecting TRON.

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 explains the tool returns a 15-min handle that should be forwarded to send_transaction, indicating the workflow. It also specifies which chains are supported and that TRON is rejected. However, it does not explicitly mention when not to use this tool versus alternatives like prepare_btc_send for simple sends, which would improve guidance.

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