locker_ackFree, owner-signed. Ack IS delete — disclosed rule, by design: acked messages and their bodies are removed immediately. Unknown ids are silently skipped.
| Name | Required | Description | Default |
|---|---|---|---|
| nonce | Yes | Nonce from locker_nonce (single-use; expires in 5 min). | |
| address | Yes | EVM wallet address (0x…, the mailbox identity). | |
| signature | Yes | EIP-191 wallet signature over the exact nonce string. | |
| message_ids | Yes |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries full burden and does exceptionally well: it discloses the destructive nature ('removed immediately'), authentication ('owner-signed'), cost ('Free'), and edge-case behavior ('Unknown ids are silently skipped'). This goes far beyond what the schema alone would convey.
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 three short sentences, front-loaded with the most critical fact ('Ack IS delete') and no filler. Every sentence delivers meaningful information: cost/auth, destructive semantics, and edge-case behavior.
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 destructive tool with no annotations and no output schema, the description covers the essential behavioral aspects: immediate deletion, ownership, and handling of unknown IDs. However, it does not specify whether only 'read' messages can be acked, nor does it describe error behavior for invalid signatures or nonce expiry, which are minor but relevant gaps.
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?
Schema description coverage is 75%, so the baseline is 3. The description adds context like 'owner-signed' and 'Unknown ids', but it does not add syntax or format details for the parameters beyond what the schema already provides (e.g., nonce from locker_nonce, EIP-191 signature).
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 title clearly states 'Acknowledge (= delete) read messages' and the description reinforces the destructive action: 'Ack IS delete — disclosed rule, by design: acked messages and their bodies are removed immediately.' This is a specific verb+resource with explicit semantics, clearly distinguishing it from locker_read (non-destructive) and locker_send.
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 implies usage through the 'Ack IS delete' warning and the 'owner-signed' requirement, but it doesn't explicitly say when to use this tool versus alternatives like locker_read or locker_checkpoint. No exclusions or alternatives are named, so guidance remains implied rather than explicit.
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.