practice_sellSells a practice position at what the chain would really pay for it this block, and books the profit or loss. A token that cannot be sold for real cannot be sold here either. Needs a key: see https://docs.swarm0x.sh/agents/
| Name | Required | Description | Default |
|---|---|---|---|
| token | Yes | The token to sell. | |
| percent | No | How much of the position. All of it when left out. |
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description adds the key requirement and the real-sellability constraint, which are not in the annotations. It also clarifies that it books profit or loss. However, it does not describe the full side effects or return behavior. Since annotations already indicate mutation (readOnlyHint=false), the description adds useful context beyond the structured fields.
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 action and result, followed by a constraint and a key requirement. There is no fluff or redundancy, and every sentence adds value.
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?
The description explains the purpose and key constraints but does not mention the return value or any consequences beyond booking profit/loss. Since there is no output schema, the description should hint at what the tool returns, but it is absent. It also does not clarify prerequisites beyond the key. This is a gap for an agent to fully understand the tool's behavior.
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 input schema fully describes both parameters with 100% coverage. The description adds no additional parameter-specific meaning; it only restates the general action. Thus, the baseline of 3 applies as the description does not exceed the schema's documentation.
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 sells a practice position at the real chain price and books profit or loss. It uses a specific verb and resource, and the constraint about tokens not sellable for real distinguishes it from real selling. It is distinct from practice_buy and prepare_sell by implying actual execution.
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?
The description gives a partial usage condition (token must be sellable for real) but does not explicitly compare with alternatives like practice_buy or prepare_sell. The use case is implied by the name and the sibling context, but there is no explicit when-to-use versus other tools.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
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