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

Annotations already cover safety (readOnly, idempotent, non-destructive, closed world), so repetition of 'Reads only' earns nothing. Beyond that, the description discloses ordering (oldest first), the composition of returned messages (user messages, agent answers/questions, system notices), and the pagination semantics of after — genuine behavioral traits not present in the 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 compact sentences, front-loaded with purpose followed by the pagination cue, with no redundant or filler content.

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?

There is no output schema, so the description carries the burden of describing return content — which it does by enumerating the message types and their order. Minor gaps remain: the limit parameter's role in paging and the absence of workspace_id guidance are left entirely to the schema, but nothing critical to invoking the tool is missing.

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 75%: task_id, after, and workspace_id are documented in the schema, while limit has only min/max bounds and no prose. The description's note on after ('read only newer messages') marginally clarifies the schema's own wording but adds no format or edge-case detail. Baseline 3 is appropriate when the schema does most of the work.

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 verb and resource (read the conversation of a task) and enumerates what the conversation contains, which distinguishes it from metadata-oriented siblings like get_task and list_tasks. It also names the originating tool (start_task), anchoring the resource. It stops short of explicitly contrasting itself with the closest sibling.

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 implies usage by tying the tool to tasks started with start_task and gives an operational cue for polling ('Pass after to read only newer messages'). However there is no explicit when-to-use versus when-not guidance, and no mention of alternatives such as get_task for task metadata (which is implied by the call itself).

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