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

With annotations covering the safety profile (readOnlyHint=false, destructiveHint=false, openWorldHint=true), the description adds real context beyond them: human escalation is possible, replies arrive within about a minute while status is 'working', and proposed actions are gated behind an id+hash approval pair. It does not say what happens to a conversation if abandoned or whether approvals are single-use.

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?

Front-loads what the tool is before the per-action mechanics, and every sentence carries information. The compressed semicolon-clause style makes the message/read split slightly harder to parse than it needs to be, but nothing is padded.

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 6-parameter tool with no output schema, the description still explains the read return shape (status, newest reply, actions awaiting approval) and the full approval lifecycle. Missing only edge behavior such as what an expired or unknown conversationId does.

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 only 17%, so the description must compensate, and it largely does: conversationId is sourced ('from the returned conversationId'), message is the entry point, and the approveActionId/approveInputHash pairing plus denyActionId are explained as an approve/deny mechanic. The 'message' vs 'read' action enum values are not individually defined, which is the residual gap.

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?

Names a specific resource (Runtime's support agent) and the concrete situations it handles: errors, a sandbox that will not start, billing, how-to, plus escalation to a person. This is clearly distinguishable from the surrounding runtime_sandbox_*, runtime_billing-adjacent and docs siblings.

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?

Gives an actionable flow: 'Start with message; continue with the returned conversationId', and states the precondition for running a proposed action (approveActionId together with its approveInputHash) versus declining it (denyActionId). It does not compare against siblings such as runtime_docs_read for how-to questions, which is the one obvious alternative left unaddressed.

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