a4a_inbox_next

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

With no annotations, the description carries the full behavioral burden and does so: 300s lease duration, expired leases become unknown and are NOT auto-redelivered, receiver_unavailable means no receiver rather than empty inbox, and file references are replaced with safe placeholders with an opaque attachment handle. This is unusually rich disclosure of edge cases and side effects.

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?

Front-loads the core action in the first sentence, then layers critical caveats. Nearly every sentence earns its place, though the cluster of file-handling caveats makes it slightly dense and could be tightened.

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 zero-param, zero-annotation, no-output-schema tool, the description supplies everything needed to invoke and follow up correctly: lease semantics, completion handoff, failure semantics, file handling, and mode restriction. No essential context is missing.

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 tool takes zero parameters and schema coverage is 100%, so there is nothing to disambiguate at the parameter level. Baseline of 4 applies; the description's mention of seq and lease_token refers to return values rather than inputs.

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 ('Lease'), a precise resource ('one authorized message'), and a scope limit ('for 300 seconds'). An agent can immediately tell this is the inbox polling/claiming primitive and distinguish it from sibling tools like a4a_inbox_status and a4a_inbox_complete.

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?

Explicitly routes the agent: call a4a_inbox_complete only after processing, use a4a_open_file for attachments, and use a4a_dialogue_open instead when in dialogue mode. It also states when this tool is disabled, which is exactly the when-not guidance agents need.

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