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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description still adds real value by scoping the return content ('full numbers and summaries') and stating an exclusion ('No recordings'), though it says nothing about pagination behavior beyond the schema's cursor note.

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 compact sentences, front-loaded with the identity of the resource, then the payload and the exclusion. No filler or redundant restatement of the title.

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?

With no output schema, the description carries the burden of describing return values, and it does so by naming messages, placed calls, numbers and summaries, plus the no-recordings caveat. Only pagination/response-shape detail is left implicit, which the cursor parameter partly covers.

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 100%, so both parameters are already documented, including that cursor is the nextCursor for older messages. The description adds no format or syntax detail beyond the schema, so the baseline 3 applies.

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 names a specific verb and resource ('One OsmO chat by conversationId') and enumerates the payload ('its messages and the calls it placed, with full numbers and summaries'), which clearly separates it from list_chats and get_call. It stops short of explicitly naming a sibling to contrast with, so it lands just under 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?

Usage is only implied: the schema notes the conversationId comes from list_chats, which hints at the list-then-fetch flow. The description itself gives no explicit when-to-use or when-not-to-use guidance versus list_chats or get_call.

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