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MP025: useless-qualifier

Marketing words like "simply" or "powerful" add no signal.

At a glance
Category description
Default severity note
Auto-fixable no
LLM-gated no
Stable since v0.1.0

What this rule checks

mcpolish runs a regex over the description for empty qualifier words. The default list:

simply, just, very, really, basically, essentially, obviously,
actually, powerful, easy, simple, convenient, useful, helpful,
great, awesome, perfect

If any of these appear, MP025 fires once for the tool and the message lists the offenders.

Why it matters

Words like "simply", "powerful", "useful" are marketing copy. They describe how the author feels about the tool, not what the tool does. The agent needs functional content: what input it takes, what output it returns, when to pick it. Marketing words eat description budget without paying it back in selection accuracy.

Wang et al. (2026) section 4.5 lists this pattern as a smell with a small but consistent regression.

Example: code that triggers this rule

@mcp.tool()
def helper(x: int = 0) -> int:
    """Use this when the user wants a simply powerful and very useful helper.
    Returns int."""
    return x

simply, powerful, very, useful all match. MP025 fires.

Example: how to fix it

@mcp.tool()
def add_one(x: int = 0) -> int:
    """Use this when the user wants the integer plus one.

    Args:
        x: The starting integer. Example: 41.

    Returns: x + 1.
    """
    return x + 1

Concrete capability statements replace the qualifiers.

Configuration

MP025 has no knobs in v1. To skip the rule entirely:

[tool.mcpolish]
ignore = ["MP025"]

When to disable this rule

If your domain uses any of these words as terms of art (a "simple" data type, a "powerful" auth role), MP025 will fire on the legitimate uses. Disabling is reasonable. The rule is note severity by default for this reason.

How the check works under the hood

mcpolish runs a single regex over the description text. Any match anywhere fires the rule. The diagnostic message lists the deduplicated offenders.

  • MP020 description-too-short: short descriptions often hide behind a qualifier.
  • MP024 jargon-density: the opposite problem (too much jargon, not enough plain language).

References