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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint false, covering safety. The description adds meaningful behavioral context: determinism, inclusion of retries and reserve budget, detection of impossible budgets and inversions, and pricing ($0.002 per call). This goes beyond annotations, though it does not describe error behavior or return structure, which would be useful.

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 compact: two substantive sentences plus a pricing note. The main purpose is front-loaded, and every sentence contributes—explaining what it does, when to use it, and the cost. No filler or redundancy.

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?

While the tool is conceptually simple (2 params), it performs complex logic and has no output schema. The description fails to specify the return format (e.g., what the allocated timeouts look like) or behavior on impossible budgets (does it fail, return an error, or propose alternatives?). This is a significant gap for an agent that needs to know what to expect from the invocation.

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 0%, so the description must compensate. It does not explicitly define the two parameters 'nodes' and 'deadline_ms'. While the phrase 'dependent agent calls' implies nodes are the call chain and 'end-to-end latency budget' implies deadline_ms, this is indirect and leaves the structure of nodes unspecified. The description adds minimal semantic value beyond what the parameter names suggest.

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 clearly states the tool's purpose: 'Deterministic end-to-end timeout allocation across dependent agent calls, including retries and reserve budget.' It also mentions detecting impossible latency budgets and timeout inversions, which distinguishes it from sibling planning tools like retry_backoff_planner and rate_limit_budget. The verb 'allocate' with a specific resource makes the action and scope unambiguous.

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?

Explicit guidance is provided: 'Use this tool when allocate a finite end-to-end latency budget across a call chain before execution' and 'Do not use it for unrelated general knowledge or unsupported legal, identity, sanctions, fraud, contractual, or regulatory adjudication.' This tells the agent exactly when to invoke it and what it is not for, though it does not name specific alternative tools.

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