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

With no annotations provided, the description carries the behavioral burden. It does disclose two useful traits: events are append-only and results are in timeline order. However, it omits other behavioral details like pagination behavior, the meaning of the export flag, or what happens when stream_id is null.

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?

The description is a single sentence with no filler. 'Append-only' and 'timeline order' are both high-signal qualifiers, and the core purpose is front-loaded.

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?

The output schema and partial parameter descriptions reduce the burden on the tool description. Still, the description leaves important context unstated: stream_id is optional, export changes the response shape, and there is no mention of when to prefer this over related list tools.

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 67% (4 of 6 parameters described), but the description itself adds no parameter semantics. The uncovered parameters (limit, offset) are simple, but the description does not compensate for the moderate coverage gap or explain the stream filter in terms of the schema's stream_id.

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 action ('List') and resource ('append-only events for a stream'), with an ordering qualifier ('timeline order'). It is clear enough to be distinguished from the write-oriented sibling event_append, though it does not explicitly name alternatives or clarify that stream_id is optional.

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 gives no guidance on when to use this tool versus alternatives such as process_run_events or event_append. There are no explicit when-to-use conditions, exclusions, or alternative tool references.

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