Adjust your lineup before contest locks by specifying exactly 15 players with positions and captain. Validation rules match submit_lineup.
Update your lineup before contest locks. Same validation rules as submit_lineup.
| Name | Required | Description | Default |
|---|---|---|---|
| contest_id | Yes | The contest ID | |
| players | Yes | Array of exactly 15 players (11 starting + 4 bench) | |
| lineup_name | No | Name for your lineup | My Lineup |
| banter | No | Updated trash talk |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the burden. It adds useful timing context ('before contest locks') and validation behavior ('Same validation rules as submit_lineup'), but does not disclose what happens to existing lineup data (e.g., full replacement vs partial update) or any side effects. This is sufficient for a basic update tool but lacks deeper behavioral detail.
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 extremely concise: two sentences, front-loaded with the action and timing, followed by a reference to validation. Every word earns its place with no redundancy or filler.
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 4 parameters, no output schema, and no annotations, the description is reasonably complete. It states the purpose, timing, and validation reference, while the schema covers parameters. It could mention what the response looks like or prerequisites, but for a simple update operation it is adequately 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 input schema description coverage is 100%, so the baseline is 3. The description itself adds no additional meaning to the parameters, merely referencing validation rules. It does not compensate beyond the schema, which already describes each parameter clearly.
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's purpose: 'Update your lineup before contest locks.' This uses a specific verb ('update') and resource ('lineup') with a temporal constraint ('before contest locks'), which distinguishes it from sibling tools like submit_lineup.
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 provides clear context for when to use the tool ('before contest locks') and references submit_lineup for validation rules, implying a distinction. However, it does not explicitly contrast with submit_lineup or other alternatives, so it falls short of full explicit 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.