request_sync

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

Annotations indicate a mutation (readOnlyHint=false) and potential side effects (openWorldHint=true). The description adds behavioral context about anchoring behavior when from_timestamp is omitted, which is not covered by annotations.

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?

Two sentences, no wasted words. The purpose is front-loaded and the parameter behavior is explained succinctly.

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 simple request tool with no output schema, the description adequately covers the action and parameter behavior. However, it lacks mention of return values, error conditions, or prerequisites (e.g., needing the chat to exist in cache).

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?

Input schema has 100% parameter descriptions, and the description adds meaning for from_timestamp by explaining the anchoring behavior. This goes beyond the schema's bare type definition.

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?

Description clearly states the action ('backfill history for a chat') and resource ('chat'), distinguishing it from sibling tools like get_chat or list_messages which are read-only or list operations.

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 for backfilling historical messages but does not explicitly specify when to use this tool over alternatives like get_chat or list_messages. The behavior when from_timestamp is omitted is explained, but no guidance on prerequisites or contexts.

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