Skip to main content
Glama
wisdomrock

code-context-gate

by wisdomrock

code-context-gate

An MCP server that acts as a context-aware code retrieval broker for AI coding agents. It sits between the agent and your codebase, enforcing backpressure so the agent never receives more context than it can use.


Why use it?

Without a gate, AI agents call raw grep/find/cat on source files. On a large codebase that means:

  • A single broad search returns 800 lines from 60 files — flooding the context window

  • Irrelevant comments, tests, and vendored code push the signal out of the model's attention

  • There is no token budget, no relevance ranking, and no guidance on how to narrow a bad query

code-context-gate solves this with four disciplined tools that rank, gate, and budget every result before it reaches the agent. Over-broad queries get a structured refine refusal with a per-directory hit distribution and actionable suggestions — so the next call is deterministic.

Scenario

Without gate

With gate

Broad search ("auth")

800 hits across 60 files, full context dump

Refusal with distribution; agent narrows to src/auth/ in one round-trip

Large codebase (500+ files)

Agent reads several wrong files before finding the right one

locate returns the 3 most relevant paths

Cross-file relationships

Must read every candidate file to infer callers

explore returns the call chain directly

Path traversal

No protection

resolveSafe() hard-blocks any path outside project root

Relationship to codebase-memory-mcp

code-context-gate can connect to a graph backend (codebase-memory-mcp or codegraph) for semantic symbol lookup and architecture overviews. But the gate's core value — ranking, backpressure, token budgeting, block expansion — is its own, independent of any graph backend. Even with --graph-backend none, it outperforms raw file access on any codebase where result volume is a concern.

codebase-memory-mcp     ← semantic understanding (what code MEANS)
        ↑ consumed by
code-context-gate       ← budget discipline (HOW MUCH reaches the agent)
        ↑ consumed by
AI agent

Related MCP server: projscan

How it works

Every tool call flows through the same pipeline:

Tool call (locate / read / explore / search)
  └─ Dispatcher         — routes by query shape (symbol → graph, phrase → merge, pattern → fileio)
       ├─ Graph adapter  — codebase-memory-mcp or codegraph (optional)
       └─ FileIO adapter — async line-by-line file scan with gitignore support
            └─ Shaper   — BM25 lexical scoring + kind weighting → ranked ResultItem[]
                 └─ Gatekeeper — enforces maxFiles / maxHits / maxTokens / minRelevance
                      └─ OkEnvelope  (results fit budget)
                      └─ RefineEnvelope  (too broad — includes distribution + suggestions)

Query shape routing in the dispatcher:

Query shape

Example

Strategy

Symbol (single word)

OrderHandler

Graph first → FileIO fallback on miss

Phrase (has spaces)

payment retry logic

FileIO + graph merged, deduped by file:line

Pattern (regex chars)

retry.*count

FileIO regex scan only


Installation

npx code-context-gate --project-root /path/to/your/project

Or install globally:

npm install -g code-context-gate
code-context-gate --project-root .

MCP Configuration

Add to your MCP client config (e.g. Claude Desktop claude_desktop_config.json or Claude Code .mcp.json):

{
  "mcpServers": {
    "code-context-gate": {
      "command": "npx",
      "args": ["code-context-gate", "--project-root", "/path/to/project"]
    }
  }
}

With a graph backend

{
  "mcpServers": {
    "code-context-gate": {
      "command": "npx",
      "args": [
        "code-context-gate",
        "--project-root", "/path/to/project",
        "--graph-backend", "codebase-memory-mcp"
      ]
    }
  }
}

CLI flags

Flag

Default

Description

--project-root

(see below)

Root directory to search within

--config

(none)

Path to a JSON config file

--graph-backend

codebase-memory-mcp

codebase-memory-mcp, codegraph, or none

--debug

false

Write structured JSON logs to stderr

Project root resolution order

  1. --project-root CLI flag

  2. CODE_CONTEXT_GATE_ROOT environment variable

  3. process.cwd() — the working directory of the process that launched the server

For stdio-mode MCP clients (Claude Code CLI, Cursor, etc.) option 3 already points at the correct project root. For GUI clients (Claude Desktop) set the env var in your MCP config:

{
  "mcpServers": {
    "code-context-gate": {
      "command": "npx",
      "args": ["code-context-gate"],
      "env": { "CODE_CONTEXT_GATE_ROOT": "/path/to/your/project" }
    }
  }
}

Tools

locate — find where something lives

Returns file paths and line ranges only — no source bodies. Use first, before read.

{ "query": "OrderHandler", "kind": "definition", "scope": "src/" }

Parameter

Type

Description

query

string

Symbol name or concept

kind

definition | reference | any

Filter by result kind (default: any)

scope

string

Subdirectory to restrict the search

max_results

number

Override the default hit cap

read — get the actual source

Reads a symbol by name or an explicit file:start-end range. Block-expands to enclosing function/class boundaries. Size-bounded so a single call never dumps an entire file.

{ "target": "OrderHandler.handle" }
{ "target": "src/payments/OrderHandler.ts:142-179", "expand": false }
{ "target": "src/config.ts" }

Parameter

Type

Description

target

string

Symbol name or file:start[-end]

expand

boolean

Expand to enclosing block (default: true)

max_tokens

number

Token budget for the response

The sanctioned replacement for grep. Always ranked, gated, and token-budgeted.

{ "pattern": "PathDeniedError", "scope": "src/" }
{ "pattern": "export.*function", "regex": true, "max_hits": 20 }

Parameter

Type

Description

pattern

string

Keyword or regex pattern

regex

boolean

Treat pattern as regex (default: false)

scope

string

Subdirectory to restrict the search

exclude

string[]

Subdirectories to skip

max_hits

number

Override the default hit cap

max_tokens

number

Token budget for snippets

force

boolean

Bypass gating (use sparingly)

explore — understand structure and relationships

Answers structural questions: callers, callees, dependencies, blast radius, architecture overview. Requires a graph backend for full results; falls back to a file scan summary when no graph is available.

{ "question": "what calls resolveSafe", "anchor": "resolveSafe", "relation": "callers" }
{ "question": "overview of the payments module", "relation": "overview" }
{ "question": "what would break if I change UserSession", "relation": "impact" }

Parameter

Type

Description

question

string

Natural-language structural question

anchor

string

Symbol to anchor the query

relation

callers | callees | dependencies | impact | overview | auto

Relationship type (default: auto)


Backpressure

When a query is too broad, tools return a refine envelope instead of overwhelming the agent:

{
  "status": "refine",
  "reason": "breadth",
  "summary": { "totalFound": 340, "files": 48, "estTokens": 28000, "topScore": 0.21 },
  "distribution": [
    { "dir": "src/auth", "hits": 120 },
    { "dir": "src/core", "hits": 80 }
  ],
  "suggestions": [
    { "action": "narrow_scope", "arg": "src/auth", "wouldYield": 120 },
    { "action": "use_force", "hint": "Set force:true to bypass gating" }
  ],
  "refusalCount": 1
}

Refusal reasons:

Reason

Condition

breadth

Unique files > maxFiles (default 25)

volume

Hit count > maxHits (120) or estimated tokens > absoluteMaxTokens (24 000)

relevance

Top BM25 score below minRelevance (0.35)

compound

Two or more of the above

Deadlock cap: after maxRefusals (default 3) consecutive refusals, the gate opens automatically.
Compound margin: single-axis near-misses within 15% of a threshold pass through without refusal.


Config file

Place a JSON file anywhere and pass it with --config:

{
  "gates": {
    "maxFiles": 25,
    "maxHits": 120,
    "maxTokens": 6000,
    "minRelevance": 0.35
  },
  "scan": {
    "excludeDirs": ["node_modules", "dist", ".git"],
    "respectGitignore": true
  }
}

Full config schema (all fields optional — shown with defaults):

{
  "gates": {
    "maxFiles": 25,
    "maxHits": 120,
    "maxTokens": 6000,
    "minRelevance": 0.35,
    "compoundMargin": 0.15
  },
  "limits": {
    "maxRefusals": 3,
    "absoluteMaxTokens": 24000
  },
  "estimation": {
    "charsPerToken": 3.5
  },
  "scoring": {
    "weights": {
      "kind": 0.30,
      "lexical": 0.25,
      "proximity": 0.20,
      "shape": 0.15,
      "recency": 0.10
    }
  },
  "backend": {
    "graph": "codebase-memory-mcp"
  },
  "scan": {
    "excludeDirs": ["node_modules", "dist", "build", "target", ".venv", "vendor", ".git"],
    "respectGitignore": true
  }
}

Logging

All tool activity is written as newline-delimited JSON to code-context-gate.log in the project root. Pass --debug to also stream logs to stderr.

Log events

Event

Source

Key fields

What it tells you

tool_call

server.ts

tool, args

Every inbound MCP tool call with its arguments

dispatch

dispatcher.ts

query, shape, graphAvailable

Query shape classification and whether graph is reachable

fileio_scan

fileio.ts

scope, patternType

When a file walk starts, what directory and pattern type (string|regex)

graph_search

graph.ts

backend, count

Graph search completed; how many results the backend returned

graph_search_error

graph.ts

backend, error

Graph search failed silently (previously swallowed)

graph_architecture

graph.ts

backend, hasResult

Architecture call completed and whether a non-empty summary was returned

graph_architecture_error

graph.ts

backend, error

Architecture call failed

dispatch_result

dispatcher.ts

strategy, count

Final strategy used (graph_symbol, fileio_only, fileio+graph_merged, etc.) and total hits

dispatch_graph_miss

dispatcher.ts

query, shape

Graph returned 0 results for a symbol query; falling back to FileIO

gate

server.ts

tool, pass, reason

Gate decision — passed or refused, and why

tool_result

server.ts

tool, returned, estTokens

How many results were returned and their estimated token cost

tool_error

server.ts

tool, error

Unhandled tool exception

Reading the log

A typical symbol lookup with graph hit:

{"ts":"...","event":"tool_call","tool":"locate","args":{"query":"resolveSafe","kind":"definition"}}
{"ts":"...","event":"dispatch","query":"resolveSafe","shape":"symbol","graphAvailable":true}
{"ts":"...","event":"graph_search","backend":"codebase-memory-mcp","count":2}
{"ts":"...","event":"dispatch_result","query":"resolveSafe","strategy":"graph_symbol","count":2}
{"ts":"...","event":"gate","tool":"locate","pass":true,"reason":null}
{"ts":"...","event":"tool_result","tool":"locate","returned":2}

A broad search that triggers a refusal:

{"ts":"...","event":"tool_call","tool":"search","args":{"pattern":"export"}}
{"ts":"...","event":"dispatch","query":"export","shape":"symbol","graphAvailable":true}
{"ts":"...","event":"graph_search","backend":"codebase-memory-mcp","count":148}
{"ts":"...","event":"dispatch_result","query":"export","strategy":"graph_symbol","count":148}
{"ts":"...","event":"gate","tool":"search","pass":false,"reason":"breadth"}
{"ts":"...","event":"tool_result","tool":"search","returned":0}

Source structure (src/)

File

Role

cli.ts

Entry point — parses CLI flags, loads config, starts the server

server.ts

MCP server — registers the four tools, wires dispatch → shape → gate → respond

dispatcher.ts

Routes queries by shape to graph and/or FileIO; merges and deduplicates results

shaper.ts

BM25 lexical scoring + kind weighting → ranked ResultItem[]; trim() for token budgeting

gatekeeper.ts

Enforces backpressure limits; returns RefineEnvelope with distribution and suggestions on failure

config.ts

Zod-validated config loader; resolves project root from flag → env var → CWD

logger.ts

Append-only JSON line logger to code-context-gate.log; never crashes the server on write failure

types.ts

Shared types and Zod input schemas for all four tools

adapters/fileio.ts

Filesystem adapter — scan(), readLines(), expandBlock(), resolveSafe()

adapters/graph.ts

Graph adapters — CodebaseMemoryAdapter, CodegraphAdapter, NullAdapter; createGraphAdapter() factory

Result scoring

Each result gets a composite score before ranking:

score = kindScore × 0.30 + BM25lexical × 0.25 + graphScore × 0.45

Kind weights:

Kind

Weight

definition

1.0

call, reference

0.7

unknown

0.5

test

0.3

comment, string

0.2


Graph backends

Backend

Launch command

Adapter

codebase-memory-mcp

npx -y codebase-memory-mcp --project-root <root>

CodebaseMemoryAdapter — calls search_code and get_architecture

codegraph

npx -y codegraph <root>

CodegraphAdapter — calls search and architecture

none

(not launched)

NullAdapter — FileIO only, all tools still work

Both graph backends are optional. Without one, all four tools work using FileIO only.


Agent Instructions (CLAUDE.md)

This repo ships a CLAUDE.md that Claude Code and compatible agents load automatically. It routes all code discovery through code-context-gate and prohibits direct calls to lower-level tools like codebase-memory-mcp.

When an agent session starts it first probes code-context-gate with a lightweight locate call:

  • Server responds → the four tools are used for all code access

  • Server unavailable → the agent stops and prompts the user to enable code-context-gate or re-enable the cbm-session-reminder fallback hook

Re-enabling the fallback hook

If you want agents to fall back to raw codebase-memory-mcp calls when code-context-gate is not running, add to ~/.claude/settings.json:

{
  "hooks": {
    "SessionStart": [
      { "matcher": "startup", "hooks": [{ "type": "command", "command": "~/.claude/hooks/cbm-session-reminder" }] },
      { "matcher": "resume",  "hooks": [{ "type": "command", "command": "~/.claude/hooks/cbm-session-reminder" }] },
      { "matcher": "clear",   "hooks": [{ "type": "command", "command": "~/.claude/hooks/cbm-session-reminder" }] },
      { "matcher": "compact", "hooks": [{ "type": "command", "command": "~/.claude/hooks/cbm-session-reminder" }] }
    ]
  }
}

Requirements

  • Node.js 20+

  • No native build tools required


License

MIT © 2026 wisdom rock — see LICENSE for full text.

A
license - permissive license
-
quality - not tested
B
maintenance

Maintenance

Maintainers
Response time
Release cycle
Releases (12mo)
Commit activity

Resources

Unclaimed servers have limited discoverability.

Looking for Admin?

If you are the server author, to access and configure the admin panel.

Related MCP Servers

  • A
    license
    A
    quality
    B
    maintenance
    An MCP server that indexes reference repositories and provides tools for AI coding agents to retrieve lossless code context, enabling reasoning over codebases larger than the agent's context window.
    Last updated
    8
    2
    Apache 2.0

View all related MCP servers

Related MCP Connectors

  • Persistent memory and cross-session learning for AI coding assistants (hosted remote MCP).

  • An MCP server that gives your AI access to the source code and docs of all public github repos

  • A comprehensive Model Context Protocol (MCP) server that enables AI assistants to interact with yo…

View all MCP Connectors

Latest Blog Posts

MCP directory API

We provide all the information about MCP servers via our MCP API.

curl -X GET 'https://glama.ai/api/mcp/v1/servers/wisdomrock/code-context-gate'

If you have feedback or need assistance with the MCP directory API, please join our Discord server