Read chat history

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

Annotations already declare readOnly/idempotent/non-destructive/openWorld, so the safety profile is covered. The description adds genuinely new behavioral facts annotations cannot express: results are ordered newest first and bodies are truncated to previews by default, with the rationale for that default. Pagination behavior and response shape are not disclosed, keeping it short of a 5.

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, zero filler, and the resource plus ordering are front-loaded before the truncation caveat. Every clause carries information the agent needs.

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 read-only tool with a fully documented schema and no output schema, the description covers the essentials an agent needs: scope, ordering, and the preview default. It omits paging guidance (the schema mentions next_cursor) and any hint of the returned message shape, but complexity is low enough that these are minor 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 coverage is 100%, so the baseline is 3; the description earns above that by explaining WHY `full` defaults off — a whole long chat mostly wastes context — which directly informs the most consequential parameter decision. The remaining four parameters get no added meaning beyond their schema descriptions.

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 resource and scope: messages from ONE chat, returned newest first. That verb+resource+ordering is unambiguous and distinct from list_chats/get_chat. It does not, however, differentiate itself from the sibling `search`, which also returns messages, leaving the boundary between browsing one chat and searching all chats to inference.

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?

There is no when-to-use or when-not-to-use statement and no alternative is named, despite `search` being an obvious competing tool for retrieving messages. The only implicit steer is the preview default, which hints at casual browsing rather than targeted retrieval, but this is left unstated.

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