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

Beyond the annotations, the description discloses substantial behavior: the output is unsigned bytes, the server never holds keys, the schedule uses wait_for_expiry so nothing moves until the deadline and auto-executes then, the buyer is the schedule admin and can delete it before the deadline, and the split is an atomic 98/2. This is exactly the context an agent needs to reason about a two-phase prepare/sign flow.

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?

Five sentences, front-loaded with the core action and then layering lifecycle, safety, and output details. Dense but each sentence carries real information; a small amount of the on-chain mechanism detail could be trimmed without loss.

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 compensates by stating the return is unsigned bytes for the buyer's wallet, and it covers the full lifecycle (prepare, sign, auto-execute, cancellation window, verification). Nothing an agent needs to invoke this correctly appears to be 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?

Schema description coverage is 100%, so all six parameters are already documented (amount_hbar, deadline_iso with 61-day cap, milestone_id memo limit, buyer key as admin key, etc.). The description adds the 98/2 split context around the amount but does not materially extend the per-parameter semantics, so the baseline 3 applies.

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 states a specific verb and resource: 'Build the UNSIGNED scheduled-payment bytes for a no-escrow milestone commitment.' It clearly distinguishes itself from siblings by naming the counterpart tool (verify_milestone_commit) and by scoping to no-escrow milestone commitments rather than generic tips or purchases.

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?

It gives a clear flow: the buyer signs in their own wallet, and 'the worker verifies the commitment with verify_milestone_commit before starting work,' which routes the agent to the next step. It does not explicitly state when NOT to use it (e.g., escrow-based commitments or other prepare_* variants), so it falls just short of full when/when-not guidance.

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