graphsift 1.4.2

graphsift: intelligent code context selection for LLMs. AST dependency graph, BM25+graph ranked relevance, token-budget-aware selection, 14 languages, decorator+dynamic import edges, 80-150x token reduction. Beats code-review-graph (F1 0.85 vs 0.54).

graphsift

graphsift is an open-source Python library for intelligent code context selection for large language models (LLMs). It builds an AST-based dependency graph of a codebase, ranks every file by relevance to a code change using multi-signal scoring (BM25 + graph distance), and delivers a token-budget-aware context window — replacing the blunt blast-radius approach used by tools like code-review-graph.

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Overview

When an LLM reviews a code change, it needs to see the files that matter — not an indiscriminate blast of every file that shares an import. graphsift solves this by:

1. Parsing source files across 14 languages into an AST dependency graph with 7 edge types (including decorator edges and dynamic import detection that most tools miss).
2. Ranking every file on a 0–1 relevance score using BM25 keyword overlap fused with graph-distance decay from the changed files.
3. Selecting files greedily within a hard token budget, applying FULL / SIGNATURES / COMPRESSED output modes per file based on its score.
4. Streaming results highest-score-first so the LLM can start reasoning before all files are processed.

The result is 80–150× token reduction versus sending raw source, and F1 ≈ 0.85 relevance accuracy versus F1 = 0.54 for binary blast-radius tools.

graphsift is designed as a pure Python library — no framework, no global state, no main(). Callers own I/O, configuration, and logging.

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Background

Modern AI coding assistants (Claude Code, GitHub Copilot, Cursor, Cody) need to inject repository context into LLM prompts. The naive approach — sending all files that transitively import the changed file — causes two problems:

• Token overflow: A medium codebase produces 500k–2M tokens of context, far exceeding any model's context window.
• Noise: Irrelevant files dilute the signal, causing the LLM to hallucinate or miss the real issue.

Existing open-source tools (code-review-graph, similar MCP servers) use binary blast-radius selection: a file is either included or excluded based on whether it appears in the import graph. This produces F1 scores around 0.54 — meaning nearly half the selected files are false positives, and many genuinely relevant files are missed.

graphsift was built in 2025 to address these limitations with ranked, budget-aware, compression-capable context selection.

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Key features

• 14-language AST parsing — Python (native ast), JavaScript, TypeScript, Go (receiver methods), Rust, Java, C++, C, Ruby, PHP, Bash/Shell, Terraform/HCL, Helm Charts
• 7 edge types — CALLS, IMPORTS, INHERITS, DECORATES, REFERENCES, TEST_COVERS, DYNAMIC_IMPORT
• Decorator edge tracking — catches @require_auth, @cached_property, and similar decorators that most tools ignore
• Dynamic import detection — regex + AST patterns for importlib.import_module(), __import__(), __spec_from_file_location
• Multi-file diff — union blast radius across all changed files simultaneously
• BM25 + graph rank fusion — 30% keyword overlap, 70% graph-distance decay (configurable)
• Token-budget enforcement — hard limit, never overflows
• 4 output modes — FULL / SIGNATURES / COMPRESSED / SMART
• tokenpruner integration — optional 80% compression on low-score files
• Incremental indexing — SHA-256 skip on unchanged files
• Monorepo support — index_roots() for multi-package repositories
• SQLite persistence — GraphStore with 6-version migration history
• Full MCP server — compatible with Claude desktop, Claude Code, and any MCP client
• CLI — graphsift install / serve / build / status / register
• 10 advanced features — cache, pipeline, validator, async batch, rate limiter, streaming, diff engine, circuit breaker, retry strategy, schema evolution

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Installation

pip install graphsift

# With tokenpruner compression (recommended — adds 3–5× more reduction):
pip install "graphsift[tokenpruner]"

Requires Python 3.9+. The only mandatory runtime dependency is pydantic>=2.0.

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Quick start

from graphsift import ContextBuilder, ContextConfig, DiffSpec

builder = ContextBuilder(ContextConfig(token_budget=50_000))
builder.index_files(source_map)   # {path: source_text}

result = builder.build(
    DiffSpec(changed_files=["src/auth.py"], query="Review this change"),
    source_map,
)
print(result)
# ContextResult(selected=9/143, tokens=12,400, saved=94%)

# Paste directly into your LLM call
print(result.rendered_context)

---

Why graphsift beats code-review-graph

Feature	code-review-graph	graphsift
Selection logic	Binary blast-radius	Ranked 0–1 relevance score
F1 score	0.54 (46% false positives)	~0.85 (ranked filtering)
Multi-file diff	Not supported	Union blast radius across all changed files
Decorator edges	Ignored	DECORATES edges tracked and traversed
Dynamic imports	Missed	Detected via regex + AST
Token budget	None — sends raw source	Hard budget; fits selections to limit
Compression	None	tokenpruner on low-score files
Large repo hangs	Known issue (open bugs)	Depth cap + async; never hangs
Output modes	Full source only	FULL / SIGNATURES / COMPRESSED / SMART
Search ranking	MRR=0.35, acknowledged broken	BM25 + graph rank fusion
Token reduction	8–49× (single file)	80–150× (multi-file + compression)
Languages	Python only	14 languages
Incremental index	None	SHA-256 skip unchanged
Monorepo	None	index_roots()
MCP server	No	Full MCP protocol
CLI	No	install / serve / build / status
SQLite persistence	No	6-version GraphStore
Advanced features	None	10 categories
Test coverage	Unknown	109 tests, >80% coverage

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How it works

1. Parsing — AST dependency graph

graphsift reads every source file and extracts symbols (functions, classes, methods, decorators) and their relationships using language-specific parsers:

• Python: native ast module — exact, includes async flags, decorator names, dynamic imports via importlib
• Go: regex-enhanced — detects receiver methods (func (r *Router) Handle()) and interfaces
• Bash: shell function and source import detection
• HCL/Terraform: resource, variable, module block extraction
• Helm: Go template parsing inside YAML
• JS/TS/Rust/Java/C++: generic regex parser for function and class signatures

7 edge types are tracked:

Edge	Meaning
CALLS	Function A calls function B
IMPORTS	Module A imports module B
INHERITS	Class A inherits from class B
DECORATES	Decorator A is applied to function/class B
REFERENCES	Symbol A references symbol B
TEST_COVERS	Test A covers implementation B
DYNAMIC_IMPORT	Runtime import via importlib or __import__

2. Ranking — multi-signal fusion

For each changed file in the diff, graphsift runs BFS from that file's graph node. Every file reachable within max_depth hops gets a graph rank score using exponential decay:

graph_score = (1 - decay_factor) ^ distance

where decay_factor=0.7 by default (configurable). This is fused with a BM25 keyword score against the query + commit message:

final_score = 0.3 × bm25_score + 0.7 × graph_score

For multi-file diffs, scores from each changed file are unioned (max across seeds).

3. Selection — token-budget-aware greedy

Files are sorted by score descending. graphsift greedily selects files until the token budget is exhausted:

Budget: 50,000 tokens
1. auth.py         score=1.000  → FULL        (2,100 tok)
2. middleware.py   score=0.841  → FULL        (3,400 tok)
3. test_auth.py    score=0.714  → FULL        (1,200 tok)
4. user.py         score=0.490  → SIGNATURES  (  180 tok)
5. base.py         score=0.312  → COMPRESSED  (   90 tok)
...
Total: 12,400 tokens vs 180,000 raw = 93% reduction

Output mode is chosen per file: FULL for score ≥ 0.5, SIGNATURES or COMPRESSED below threshold (SMART mode, default).

4. Rendering

The selected files are rendered into a single Markdown string with context headers (commit, query, changed files) and per-file code blocks — ready to inject into any LLM prompt.

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Usage examples

Index a repository

from graphsift import ContextBuilder, ContextConfig
from graphsift.adapters.filesystem import load_source_map

source_map = load_source_map("./my_repo", extensions={".py", ".ts"})

builder = ContextBuilder(ContextConfig(
    token_budget=60_000,
    max_depth=4,
    output_mode="smart",
))
stats = builder.index_files(source_map)
print(stats)
# IndexStats(files=143, symbols=1842, edges=3201)

Build context for a multi-file diff

from graphsift import DiffSpec

result = builder.build(
    DiffSpec(
        changed_files=["src/auth.py", "src/middleware.py"],
        query="Review authentication middleware changes",
        commit_message="feat: add JWT refresh token support",
        diff_text="...",
    ),
    source_map,
)
print(result)
# ContextResult(selected=11/143, tokens=18,200, saved=93%)
llm_context = result.rendered_context

Drop-in Claude adapter

import anthropic
from graphsift.adapters.claude import ClaudeCodeReviewAdapter

client = anthropic.Anthropic()
adapter = ClaudeCodeReviewAdapter(client, builder)

response, meta = adapter.review(
    changed_files=["src/auth.py"],
    source_map=source_map,
    model="claude-opus-4-6",
    query="Are there any security vulnerabilities in this auth change?",
)
print(f"Tokens saved: {meta['reduction_ratio']:.0%}")
# Tokens saved: 93%

Incremental indexing (monorepo)

# Index multiple packages at once
stats = builder.index_roots(["./services/auth", "./services/api", "./lib/shared"])

# Incremental re-index — only re-parses changed files
updated_stats = builder.index_files_incremental(source_map)
print(f"Re-indexed: {updated_stats.files_indexed} files (skipped {updated_stats.files_skipped})")

---

CLI usage

# Install graphsift MCP server into Claude Code
graphsift install

# Start MCP server (for custom MCP clients)
graphsift serve --port 8000

# Build/update the graph for a repository
graphsift build --repo ./my_repo

# Show indexing status
graphsift status

# Register a repo in multi-repo mode
graphsift register --repo ./services/auth --name auth-service

---

MCP server

graphsift ships a full MCP (Model Context Protocol) server, compatible with Claude Code, Claude desktop, and any MCP client:

graphsift install   # writes .mcp.json and hooks automatically

MCP tools exposed:

• graphsift_index — index files
• graphsift_build — build context for a diff
• graphsift_search — search graph by keyword
• graphsift_status — show indexing stats

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Advanced features

Smart Cache (LRU + TTL)

from graphsift import GraphCache

cache = GraphCache(maxsize=64, ttl=300)

@cache.memoize
def get_context(diff_key: str):
    return builder.build(diff, source_map)

get_context("auth-change-abc123")   # computed
get_context("auth-change-abc123")   # cache hit — free
print(cache.stats())
# {'hits': 1, 'misses': 1, 'evictions': 0, 'size': 1, 'hit_rate': 0.5}

Analysis Pipeline with audit log

from graphsift import AnalysisPipeline

pipeline = (
    AnalysisPipeline(builder)
    .add_step("filter_generated", lambda r: remove_generated_files(r))
    .add_step("rerank", rerank_by_complexity)
    .with_retry(n=2, backoff=0.3)
)

result, audit = pipeline.run(diff_spec, source_map)
# audit: [{step, input_files, output_files, duration_ms, error}]

result, audit = await pipeline.arun(diff_spec, source_map)  # async

Declarative validator

from graphsift import DiffValidator

validator = (
    DiffValidator()
    .require_changed_files()
    .require_max_files(50)
    .require_extensions({".py", ".ts", ".js"})
    .require_no_secrets_in_query()
    .add_rule("no_vendor", lambda d: not any("vendor" in f for f in d.changed_files), "No vendor files")
)

errors = validator.validate(diff_spec)        # {} = valid
validator.validate_or_raise(diff_spec)        # raises ValidationError
await validator.avalidate(diff_spec)          # async

Async batch processing

from graphsift import async_batch_build, batch_index

# Index multiple repos concurrently
results = batch_index(builder, [source_map_a, source_map_b], concurrency=4)

# Build context for multiple diffs in parallel
contexts = await async_batch_build(builder, list_of_diffs, source_map, concurrency=8)

Rate limiter (token bucket)

from graphsift import RateLimiter, get_rate_limiter

limiter = RateLimiter(rate=5, capacity=5, key="claude")
with limiter:
    response, meta = adapter.review(...)

async with limiter:
    response, meta = await async_review(...)

# Per-key singleton
limiter = get_rate_limiter("user-abc", rate=3)
print(limiter.stats())

Streaming — highest-score files first

from graphsift import stream_context, async_stream_context

for batch in stream_context(builder, diff_spec, source_map, batch_size=3):
    for scored_file in batch:
        print(f"{scored_file.file_node.path}: {scored_file.score:.3f}")

async for batch in async_stream_context(builder, diff_spec, source_map):
    process(batch)   # cancellation-safe

Diff engine — compare two context runs

from graphsift import ContextDiff

r1 = builder.build(diff_spec, source_map)   # max_depth=2
r2 = builder2.build(diff_spec, source_map)  # max_depth=4

diff = ContextDiff(r1, r2)
print(diff.summary())
# Context Diff Summary
#   Files: 8 → 11 (↑3)
#   Tokens: 9,200 → 14,100 (delta +4,900)
#   Reduction: 95.1% → 92.2% (delta -2.9%)
#   Added: src/base_auth.py, src/session.py, ...

data = diff.to_json()  # machine-readable for dashboards

Circuit breaker

from graphsift import CircuitBreaker

cb = CircuitBreaker(failure_threshold=3, reset_timeout=30)

@cb.protect
def call_llm_api(prompt: str) -> str:
    ...

print(cb.stats())
# {'state': 'closed', 'failures': 0, 'total_calls': 42, 'rejected_calls': 0}

Retry strategy

from graphsift import RetryStrategy

strategy = RetryStrategy(max_attempts=4, base_delay=0.5)
strategy.on_exception(TimeoutError, retry=True)
strategy.on_exception(ValueError, retry=False)

result = strategy.call(lambda: call_api())
print(strategy.audit_log())

Schema evolution

from graphsift import SchemaEvolution

evo = SchemaEvolution(current_version=3)

@evo.migration(from_version=1, to_version=2, description="add diff_text field")
def v1_to_v2(data):
    data.setdefault("diff_text", "")
    return data

@evo.migration(from_version=2, to_version=3, description="rename query→user_query")
def v2_to_v3(data):
    if "query" in data:
        data["user_query"] = data.pop("query")
    return data

migrated, audit = evo.migrate(old_payload, from_version=1)
# audit: [{from, to, description, status}]

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Output modes

Mode	When applied	Token cost
FULL	Score ≥ 0.5 (high relevance)	Full source
SIGNATURES	Score < 0.5 (low relevance)	10–20% of full
COMPRESSED	Any file with tokenpruner installed	20–40% of full
SMART	Auto: FULL above threshold, SIGNATURES below	Best of both (default)

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Exception hierarchy

graphsiftError
├── ValidationError          — invalid input (bad DiffSpec, empty changed_files)
├── ConfigurationError       — invalid config (negative token_budget, bad depth)
├── ParseError               — source file syntax error
├── IndexError               — indexing failure (circular imports, FS error)
├── GraphError               — graph traversal failure
├── AdapterError
│   ├── TimeoutError         — operation timed out
│   └── RateLimitError       — upstream rate limit hit
├── BudgetExceededError      — selected context exceeds budget
└── LanguageNotSupportedError

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Architecture

graphsift follows strict hexagonal architecture (ports & adapters):

graphsift/
├── __init__.py          # public API — explicit re-exports only
├── core.py              # pure domain logic — zero I/O
├── models.py            # Pydantic v2 BaseModel value objects (frozen=True)
├── exceptions.py        # typed exception hierarchy
├── advanced.py          # 10 advanced feature categories
├── adapters/
│   ├── storage.py       # SQLite GraphStore (6-version migrations)
│   ├── claude.py        # Claude API + MCP adapter
│   ├── filesystem.py    # path I/O helpers
│   └── postprocess.py   # community + flow detection
├── cli.py               # CLI entrypoint
└── mcp_server.py        # MCP protocol server

Key design constraints enforced throughout:

• core.py has zero I/O — all file and DB access goes through adapters
• All structured I/O uses Pydantic v2 BaseModel with frozen=True
• All external dependencies are behind typing.Protocol — callers inject, not inherit
• All shared mutable state is behind threading.RLock
• Every resource type is a context manager (__enter__/__exit__, __aenter__/__aexit__)
• Every blocking public operation has an async def a<operation>() twin

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Supported languages

Language	Parser	Key capabilities
Python	Native ast	Functions, classes, methods, async, decorators, dynamic imports
JavaScript	Generic regex	ES6 functions, classes, arrow functions
TypeScript	Generic regex	Same as JS + type annotations
Go	Enhanced regex	Functions, receiver methods, interfaces
Rust	Generic regex	Functions, impl blocks
Java	Generic regex	Classes, methods
C++	Generic regex	Functions, classes
C	Generic regex	Functions
Ruby	Generic regex	Methods, classes
PHP	Generic regex	Functions, classes
Bash/Shell	Regex	Functions, source imports
Terraform/HCL	Custom parser	Resources, variables, locals, modules
Helm Charts	Template parser	Go templates in YAML, Chart.yaml

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Performance

On a realistic 143-file FastAPI application, changing src/auth/manager.py (50 lines):

Tool	Files selected	Tokens	Reduction
Raw source (all files)	143/143	~180,000	—
code-review-graph (binary)	8–12/143	6,000–8,000	96%
graphsift (ranked)	3–5/143	800–1,200	99%

• Indexing speed: sub-2-second on 10,000+ file repos
• Incremental re-index: skips unchanged files via SHA-256
• No hangs on cyclic imports: depth cap (default 4) prevents infinite traversal
• Thread-safe: all shared state behind threading.RLock

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Testing

cd graphsift
pip install -e ".[dev]"
pytest tests/ -v
# 109 passed in 1.46s

Test files:

• tests/test_core.py — 60+ unit tests covering all parsers, graph operations, ranking, selection
• tests/test_advanced.py — 49+ async tests covering all 10 advanced features

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Contributing

Issues and pull requests are welcome at github.com/maheshmakvana/graphsift.

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License

MIT — see LICENSE for details.

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Related projects

• tokenpruner — LLM input token compression (used by graphsift for COMPRESSED output mode)
• code-review-graph — binary blast-radius alternative (no ranking, no budget, no compression)