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

Annotations already declare read-only, idempotent, closed-world behavior, so the description doesn't need to re-state safety. It adds genuinely non-obvious context: that the response includes the raw request/response payloads and the associated ad and conversation. Error semantics (404 not_found, 403) live in the schema rather than here, which is fine.

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 verb, zero filler. The field enumeration is dense but each item tells the agent something it would otherwise have to discover by calling the tool.

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 what comes back, and it does so by naming the major fields (tool identity, outcome, conversation, ad, request, response). Slightly more on the payload shape would make it fully self-sufficient.

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 100% and both parameters carry detailed descriptions including cross-agent and cross-company 404/403 behavior. The description only adds provenance for run_id ('Get its id from list_tool_runs'), which is a small but real addition over the schema's 'One of the agent's tool runs'.

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 a specific verb and resource ('Get one tool run of an agent') and enumerates the payload it exposes: provider/operation, outcome, conversation, ad, request and response. That enumeration makes it immediately distinguishable from list_tool_runs and get_conversation.

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 routes the agent to list_tool_runs to obtain the run_id, which is the main prerequisite for calling this tool. It doesn't state any when-not condition, but a single-record fetch has few plausible alternatives.

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