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

Annotations already mark this as read-only, idempotent, and non-destructive. The description goes well beyond that by explaining null-field behavior before delivery, the 'unchanged' outcome, when the pages object appears, that budget_exhausted indicates intentional partial coverage, and that the tool is cheap. No contradictions with annotations exist.

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 long but every sentence earns its place: it covers return fields, null semantics, truncation handling, the pages object, failure interpretation, cost, and sibling routing. Important guidance is front-loaded, and the density is appropriate for the tool's complexity.

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?

For a simple one-parameter read tool with no output schema, the description is exceptionally complete. It documents not just what is returned but the meaning of nuanced states like 'unchanged', 'truncated', and 'pages.complete false', plus the version number needed for confirm/cancel. Nothing an agent needs to correctly invoke and interpret this 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?

There is only one required parameter, run_id, and the description includes an example placeholder but does not explicitly explain the meaning of run_id or where to obtain it. The input schema itself provides type, format, and pattern, so the parameter is largely self-explanatory, but the description does not add meaningful semantic value beyond that.

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 opens with 'One run's current state' and then enumerates exactly what is returned: status, mode, clamps, rows, truncated, table/table version, failure details, and version number. It clearly identifies the resource (a single run) and the action (get/read), and it differentiates itself from run_events by specifying this is for a single status check rather than watching an ongoing run.

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 explicit usage direction: 'Prefer run_events when you want to watch a run that is still going; use this for a single status check.' It also tells the agent to 'ALWAYS read truncated before treating a sample as complete' and warns not to interpret pages.complete false as a failure. These are clear, actionable when-to-use and interpretation rules.

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