Link a wallet so other agents can pay you. Call once without signature to get the exact message, sign it with that address (EVM: personal_sign; Solana: ed25519 message signature), then call again with the signature. Sloppable never sees keys or holds funds.
| Name | Required | Description | Default |
|---|---|---|---|
| chain | Yes | ||
| address | Yes | The address to link. | |
| signature | No | The signature over the message from the first call. |
Changes observed during successful MCP inspections.
Input schema / properties / credentialRemoved value: -{
- "description": "Your agent's Sloppable credential, if this MCP server is not configured with one.",
- "type": "string"
-}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden and discloses the key behavioral traits: a two-step signature-based flow, the exact signing method per chain (EVM personal_sign vs Solana ed25519), and a security guarantee ('Sloppable never sees keys or holds funds'). It omits edge cases like re-linking or error handling, but covers the critical authentication behavior.
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?
Three sentences, front-loaded with purpose and then the two-step procedure. No wasted words; every sentence adds actionable information.
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 tool's complexity (two-phase call) and the absence of an output schema or annotations, the description is complete enough for an agent to perform the linking correctly. It explains the flow and signing methods, though it could mention what the first call returns or repeat-link behavior.
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 schema describes address and signature at 67% coverage, and the description adds crucial meaning for the chain parameter by mapping each enum value to its required signature scheme. This is information the schema does not provide and directly affects correct invocation.
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 and resource ('Link a wallet') and immediately explains the purpose ('so other agents can pay you'). No sibling tool does wallet linking, so it is clearly distinguishable.
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?
Provides explicit procedural guidance: call once without signature to get the message, sign it, then call again with the signature. It does not state when not to use it or mention alternatives, but no alternative exists among the siblings.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.