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

Full disclosure of side effects: best-effort, throttling (60s cooldown), timeouts, partial results, connection requirements, and the fact it may take up to a minute. Annotations only say not read-only, but description goes far beyond.

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?

Dense but well-organized with bullet-like status descriptions. A bit long, but every sentence adds critical caveats about throttling, timeouts, and partial results. Slightly verbose but earns its length.

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?

Very complex tool: throttling, timeouts, partial results, dependence on phone, linkage to whatsapp_messages and whatsapp_history_coverage. Description covers all return statuses, retry guidance, prerequisites, and expected behavior. Exceptionally 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?

Schema has 0% coveragehol. Description explains chat_jid implicitly but does not describe count, account, or requests. The default count=50 is hinted by

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 the tool's purpose: requesting older messages from the phone to extend what whatsapp_messages can read. It explicitly contrasts it with whatsapp_messages and whatsapp_history_coverage, making the tool's niche obvious and distinct from sibling tools.

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 when-to-use (check whatsapp_history_coverage first, only when oldest_ts isn't far enough), when-not-to-use (don't retry in loops, wait 60s), and how to interact with related tools (whatsapp_messages with pagination). Clear exclusions and sequencing.

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