buy_lot

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

Discloses key behaviors: reserves units immediately (no dry-run), auto-approves spend, and submits on-chain payment. Mentions payment in $CPU, seller price, and transit fees. This is thorough for a financial transaction tool with no annotations.

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?

Concise at about 6 sentences, with key information front-loaded (purpose, prerequisites, chain structure) and important notes (immediate reservation, cost preview) included efficiently. No 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?

Covers prerequisites, payment, side effects, and related tools. However, lacking description of the return value (e.g., transaction ID) given no output schema. Still, very complete for a complex tool.

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%, so baseline is 3. The description adds valuable context: chain structure (hub to destination), value constraint (≤ lot remaining), and lotId source. This extra detail raises the score.

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 action ('Buy units'), the resource ('OPEN lot'), and the delivery context ('to your own cell'). It distinguishes from sibling tools like quote_buy and list_my_transports by mentioning them for cost preview and tracking.

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 states the prerequisite ('Requires a session'), explains the chain parameter structure, and provides explicit when-to-use alternatives: 'preview the exact cost first with quote_buy' and 'Track delivery with list_my_transports / get_lot'. Clearly indicates lot must be OPEN.

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