item

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

With no annotations, the description carries the full behavioral burden. It discloses the return content (input, output, diffs) but does not state whether the operation is read-only, whether it requires specific permissions, or any rate limits for polling, leaving gaps for a read tool.

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, front-loaded with the purpose. The phrasing is efficient with no wasted words, though the first sentence is slightly complex due to the embedded return description.

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?

Given a simple 2-parameter tool with an output schema and full schema coverage, the description is nearly complete: it explains what it does and when to use it. The main missing element is explicit disclosure that it is a read-only operation, which would be helpful without annotations.

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 the schema already documents both parameters. The description adds minor context about the id coming from snapshot, but provides no additional meaning for the session parameter beyond the schema.

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 it retrieves one conversation item in full by id, and specifies the returned content (tool call with input, output, diffs, or any other item). It distinguishes from the sibling snapshot tool by clarifying it provides full details for on-demand viewing.

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?

Explicitly says it is for UI clients that poll snapshot with simplify and show details on demand, implying it should be used after obtaining an id from snapshot. The alternative (snapshot) is named in context, though not with an explicit 'use this instead' phrasing.

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