locker_nonceFree. Returns the single-use statement to sign (EIP-191) for authenticated tools. Expires in 5 minutes.
| Name | Required | Description | Default |
|---|---|---|---|
| address | Yes | EVM wallet address (0x…, the mailbox identity). |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden. It discloses that the nonce is free, single-use, follows EIP-191, and expires in 5 minutes—key behavioral traits beyond just 'get a nonce.' It doesn't cover edge cases like invalidation of prior nonces, but the core behavior is well explained.
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 short sentences, each with distinct information: cost ('Free'), purpose ('Returns...'), and behavior ('Expires in 5 minutes'). No wasted words.
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 tool with no output schema, the description covers the essential return value, the signing standard (EIP-191), expiry, and cost. It could mention how the nonce relates to the address, but the schema already describes the address. Sufficiently complete.
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 already provides 100% coverage for the single 'address' parameter with a clear description ('EVM wallet address (0x…, the mailbox identity)'). The tool description adds no additional parameter semantics, but the baseline for high schema coverage is 3.
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 it 'Returns the single-use statement to sign (EIP-191) for authenticated tools,' using a specific verb and resource. It distinguishes itself from siblings like locker_send or locker_status by focusing on nonce acquisition.
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 says the nonce is 'for authenticated tools,' implying it is a prerequisite for authentication, and notes the 5-minute expiry. However, it does not explicitly mention when to use it vs alternatives or any exclusions, so it falls short of a 5.
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.
Each tool has a clearly distinct purpose: send, read, ack, count, register_key, directory, nonce, capabilities, credit, checkpoint, and status cover different operations without overlap. Even similar-sounding tools like count and read are cleanly separated by scope (message count vs. message content).
All tool names follow a uniform pattern with the 'locker_' prefix and lowercase snake_case. While some postfixes are nouns (capabilities, directory, status) and others verbs (send, read, ack), the style is consistent and predictable, matching the server's domain.
11 tools is well-scoped for a messaging/storage server: each tool earns its place covering setup, messaging, payment, and account management without redundancy or bloat.
The tool surface provides complete lifecycle coverage for the mailbox system: key registration, message sending/reading/acknowledging, directory lookup, nonce generation, payment via credit, persistent checkpoint storage, and status monitoring. No obvious dead ends or missing operations for the stated purpose.