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

With no annotations, the description carries the full behavioral burden. It usefully discloses the no-payment/no-auth trait and that it is a 'live' sample returning a GO/HOLD/BLOCK decision, but says nothing about rate limits, whether results are deterministic, or the exact meaning of 'sample'.

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?

Two short sentences with the FREE/preview framing front-loaded. 'No payment required' is somewhat redundant with 'FREE,' which keeps it just short of ideal conciseness.

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 3-param preview tool with no output schema, the description tells the agent what to expect (a GO/HOLD/BLOCK decision 'same shape as gate_swap') and the payment context, but leaves the actual return structure undescribed since it only references the sibling.

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 the schema already documents all three parameters and their enums/defaults. The description adds only the context that tokens are 'demo Base' tokens and repeats the enum values, so baseline 3 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 names a specific resource (the gate_swap pre-trade GO/HOLD/BLOCK decision) and clearly frames this as a free preview variant, distinguishing it from the sibling gate_swap. It is clear what the tool returns, though the core 'action' is described as producing a sample rather than a crisply stated verb.

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 signals the free/no-payment context and 'same shape as the paid gate_swap tool,' which implies when to reach for this over gate_swap, but it never explicitly states the selection condition or when NOT to use it. Usage is left to inference from the FREE/no-payment framing.

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