conversations_history

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

readOnlyHint=true already establishes this is a safe read. Beyond that the description adds real behavioral context: CSV output, newest-first ordering, the local-midnight basis for window limits, and the rule that passing the cursor preserves the original window and page size. It does not mention permissions or rate limits.

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?

Three compact sentences, front-loaded with what the tool returns before moving to parameter mechanics. Dense but every clause carries usable information; no filler.

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?

An output schema exists, so return values need not be enumerated, and the read-only annotation covers the safety profile. The description still supplies the pagination and window semantics an agent needs to call it correctly; only include_activity_messages is left unaddressed.

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 0%, so the description carries the load, and it does so well for the two non-obvious parameters: limit's dual count/window syntax with examples ('50', '1d', '2w', '3m') and the cursor round-trip contract. channel_id is self-evident, but include_activity_messages is never mentioned, leaving one of four parameters undocumented.

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 states a specific resource and scope: messages in a channel or DM, returned as CSV, newest first. That scope implicitly separates it from conversations_replies (threads) and conversations_search_messages, but no sibling is named explicitly, so it stops short of a 5.

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?

It gives concrete operational guidance: limit accepts either a count or a window and should be left empty when a cursor is passed, and it explains when to paginate (non-empty Cursor column on the last row). It does not say when to prefer this tool over conversations_search_messages or conversations_replies, so it lacks explicit alternatives.

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