Finalizes a fully signed PSBT and broadcasts it to the Bitcoin network via mempool.space so signed transactions can be submitted for confirmation.
Finalize a fully signed PSBT and broadcast it to the Bitcoin network via mempool.space.
Tip: call earning_opportunities to see how to put your assets to work.
| Name | Required | Description | Default |
|---|---|---|---|
| psbtBase64 | Yes | Fully signed PSBT in base64 format |
Changes observed during successful MCP inspections.
v1.77.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations exist, so the description carries the burden. It usefully discloses the external broadcast route (mempool.space) and that the input must already be fully signed, but says nothing about irreversibility, failure behavior, or whether a transaction ID is returned.
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 purpose sentence is front-loaded and tight. The trailing promotional tip about earning_opportunities does not help an agent select or invoke this tool and dilutes the definition.
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 one-parameter broadcast tool with full schema coverage and no output schema, the definition should say what comes back (e.g., a txid) and what happens on rejection. Those gaps leave the post-call picture incomplete.
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?
Single parameter with 100% schema coverage, so the schema already documents psbtBase64. The description reinforces the 'fully signed' constraint but adds no format, size, or validation detail beyond the schema.
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?
States a specific verb (finalize + broadcast) and resource (fully signed PSBT) plus the routing service (mempool.space). It does not explicitly distinguish itself from close siblings like psbt_sign or broadcast_transaction, leaving the agent to infer the boundary.
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?
"Fully signed PSBT" implies the prerequisite that psbt_sign must run first, but no when-to-use/when-not or alternative is stated. The 'Tip' about earning_opportunities is a cross-sell, not usage guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.