Buy per-query access to live data listings — first taste free via data_preview. Listing: arstechnicawatch: Ars Technica Tech, IT & Hardware News (0.01 USDC/query). Platform-executes funding so you can data_session_query.
| Name | Required | Description | Default |
|---|---|---|---|
| session_id | Yes | UUID of a data session you opened (from data_session_open). |
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With annotations already marking this as non-read-only and idempotent, the description adds meaningful side-effect detail: it executes a paid funding operation, specifies the per-query cost (0.01 USDC), and states that funding is platform-executed. It aligns with the annotations and adds value beyond them.
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 two sentences front-loaded with the core purpose, then a concrete listing with pricinghol. Every phrase adds useful information; there is no filler or redundant restatement of the schema.
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 tool with one parameter, the description explains the transaction, the listing, pricing, and the downstream effect. It does not describe failure/confirmation behavior, but the simple contract and schema make the description reasonably complete.
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?
The schema fully covers the lone parameter, including format ('UUID') and origin ('from data_session_open'). The description adds no parameter-specific behavior, but schema coverage is complete, so a middle score is appropriate.
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 action — 'Buy per-query access to live data listings' — names the exact listing and price, and connects it to a follow-up tool (data_session_query). This removes ambiguity about what the tool does.
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 concrete workflow guidance: try data_preview first for a free 'taste,' then use this tool to fund a session before querying. It does not explicitly differentiate from related data_session_funding_package or attach tools, but the intended sequence is clear.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.