MCP Server¶

codekb mcp serve exposes one code bundle to an agent over the Model Context Protocol, speaking JSON-RPC on stdio.

kl4a --use codekb mcp serve ./my-code-bundle

The surface is read-only. There is no tool that writes to the bundle, so an agent cannot approve a claim, change review state, or alter the repository record. Review remains a human-controlled workflow.

Wiring it up¶

Point any MCP client at the command. For a client that reads a JSON config:

{
  "mcpServers": {
    "codekb": {
      "command": "codekb",
      "args": ["mcp", "serve", "/absolute/path/to/my-code-bundle"]
    }
  }
}

The server reports itself as codekb and negotiates protocol versions 2025-06-18, 2025-03-26, and 2024-11-05, falling back to the last of those when a client asks for something else.

Tools¶

* marks a required argument.

Tool	What it does	Arguments
`code.repo.describe`	Describe the bundle: repository record and counts	—
`code.files.search`	Search source files	`query*`, `language`
`code.symbols.search`	Search symbols	`query*`, `language`
`code.symbols.get`	One symbol with its evidence and relations	`symbol_id*`
`code.relations.search`	Search edges	`subject`, `predicate`, `object`, `resolution_status`
`code.callgraph.neighborhood`	Edges around a symbol or module	`node_id*`, `depth`
`code.tests.for_symbol`	Tests related to a symbol	`symbol_id*`
`code.change_impact`	Direct impact of changing a symbol	`symbol_id*`
`code.context`	Task-ready context for a developer agent	`task*`, `query`, `language`

Each returns JSON. The same operations are available from the shell — see the CLI Reference — so you can see exactly what an agent will get before wiring anything up.

What an agent is allowed to see¶

Retrieval is filtered by review state, not by what was mined. A claim reaches an agent unless:

it was rejected, or
it is no longer active in the bundle's lifecycle, or
it is tier 4 or above and flagged for review — those open only on an explicit approval. Deferring or commenting on such a claim leaves it closed.

The MCP surface has no more permissive path into the data.

The practical consequence is that a freshly built bundle answers thinly. That is the intended behaviour — see Knowledge & Review.

Grounding¶

The server sends instructions telling the client to answer only from the bundle and to cite the evidence attached to each claim, rather than answering from general knowledge about the codebase. Every claim carries the source span it was derived from, so an answer can always be checked against the code.

Relationship to the sopkb MCP server¶

sopkb mcp serve exposes the SOP tool surface (knowledge.*, sections.*, evidence.*, relations.*). codekb mcp serve exposes code.* only.

They are separate servers over separate bundles. Point an agent at whichever matches the question, or register both — the tool names do not collide.