kconfig-mcp

Overview Schema Source Related Servers Discussions Admin

kconfig_why_not

Explains why a Kconfig symbol cannot reach a given value by tracing unmet depends on, visible if, choice, and select conditions with file:line locations, then returns a verified minimal fix.

Instructions

Explain why a symbol isn't (or can't be) at value, and how to fix it.

Walks every unmet depends on, visible if, if block, choice and select/default condition with file:line, recursing into the symbols they name. Then searches for a minimal set of assignments and VERIFIES it by applying it to the tree - a fix is only shown if Kconfig agrees it works, along with its side effects. value: "y", "m", or "n" (why can't I turn it off?).

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "name": "<name>",
      "symbol": "<symbol>"
    },
    "name": "kconfig_why_not"
  }
}

Input Schema

Name	Required	Default
`name`	Yes
`value`	No	y
`symbol`	Yes

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Nov 10, 2026

TDQS

A3.7/5.0

Behavior4/5

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

With no annotations, the description carries the full burden and does substantial work: it discloses recursion into depends on/visible if/if/choice/select conditions, file:line reporting, minimal-assignment search, and verification by applying a candidate fix to the tree. The one gap is whether that verification mutates the live config or a scratch copy — an important side-effect question left unanswered.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with the purpose in the first sentence, then supporting mechanics in order of increasing detail. Slightly dense with backtick-heavy phrasing and line-broken clauses, but no sentence is wasted.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return values need no explanation, and the behavioral narrative is unusually rich. It falls short on the two required parameters that are never explained and on whether fix verification is a read-only simulation or a real mutation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters2/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description must compensate, and it only covers `value` ("y", "m", or "n"). It never distinguishes the two required parameters `name` and `symbol` — presumably a session name versus a Kconfig symbol, but that is guesswork for the caller.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Opens with a specific verb and resource: 'Explain why a symbol isn't (or can't be) at value, and how to fix it.' The diagnostic framing plus the clause 'while Kconfig agrees it works' makes it clearly distinct from mutating siblings like kconfig_set or the lookup-oriented kconfig_symbol.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The parenthetical '(why can't I turn it off?)' gives a concrete usage scenario for value="n", which is helpful context. However, it never states when NOT to use this tool or names an alternative (e.g. kconfig_set for actually applying a change), so the agent must infer the boundary between diagnosing and fixing.

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

Deploy Server