Frontrun MCP Server

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

With no annotations provided, the description carries the full burden of behavioral disclosure. While 'Update' implies a mutation operation, the description doesn't specify permission requirements, whether changes are reversible, potential side effects, or what happens to unspecified fields (partial vs. full updates). For a mutation tool with zero annotation coverage, this leaves significant behavioral gaps for the agent to navigate.

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 a single, efficient sentence that directly states the tool's purpose without any wasted words. It's appropriately sized for a straightforward update operation and front-loads the essential information. Every word earns its place in this minimal but complete statement.

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?

Given the tool's moderate complexity (5 parameters with nested objects), lack of annotations, and absence of an output schema, the description is minimally adequate but leaves significant gaps. It identifies the operation type but doesn't address behavioral aspects, usage context, or return values. For a mutation tool without annotations or output schema, more contextual information would be helpful for the agent.

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 has 100% description coverage, providing clear documentation for all 5 parameters and their nested structures. The description adds no additional parameter semantics beyond what's already in the schema. According to the scoring rules, when schema_description_coverage is high (>80%), the baseline score is 3 even with no param info in the description, which applies here.

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 verb ('Update') and resource ('an existing custom classification rule'), making the purpose immediately understandable. It distinguishes this from sibling tools like 'frontrun_create_rule' and 'frontrun_delete_rule' by specifying it updates existing rules rather than creating or deleting them. However, it doesn't explicitly differentiate from other update-like operations that might exist in the system.

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 no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing the rule UUID from 'frontrun_list_rules'), when not to use it (e.g., for creating new rules), or how it relates to sibling tools like 'frontrun_create_rule' or 'frontrun_delete_rule'. The agent must infer usage from the tool name and context alone.

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