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Gograph

An AST-aware structural repository graph engine and MCP server designed for AI agents. Understands Go struct embeds, public API surfaces, SQL queries, and error mapping to give agents instant codebase context without blindly grepping.

developer-toolsgoapiaiagent
By ozgurcd
21214Updated 1 day agoGoMIT

Installation

npx -y gograph

Configuration

{
  "mcpServers": {
    "gograph": {
      "command": "npx",
      "args": ["-y", "gograph"]
    }
  }
}

How to use

  1. Run the installation command above (if needed)
  2. Open your Claude Code settings file (~/.claude/settings.json)
  3. Add the configuration to the mcpServers section
  4. Restart Claude Code to apply changes

gograph

Go Report Card License: MIT Go Version Homebrew Docs

Give Go coding agents a compiler-aware map for safer refactors.

gograph builds a local structural graph of your Go repository, with optional type-checked CHA/SSA enrichment. Its CLI and MCP workflows help coding agents trace callers and interface implementations, plan change impact, and enforce architecture without embeddings or a hosted code index.

Explore the interactive no-install demo · Review the reproducible benchmark

Companion projects: Scrinium provides repository-owned, evidence-backed knowledge for coding agents, while Rulefloor protects repository-local invariants by binding them to concrete tests and detecting drift. They are independent, optional tools: Scrinium can keep Gograph structural observations and Rulefloor validation results as separate evidence without treating either as proof of unrelated behavior or global project correctness.

Gograph Demo

Static analysis; no target-code execution. Default indexing parses Go source locally and does not call application services. Descendant links and special files for extensions recognized by go/build are excluded, graph-directed source reads are confined to regular files beneath the analyzed repository, and linked/non-regular Go tool metadata (go.mod, go.sum, go.work, go.work.sum, and vendor/modules.txt) is rejected before toolchain invocation; an explicitly symlinked repository root remains supported. Applicable go.work use members must stay beneath the workspace directory, and each member directory, go.mod, and optional go.sum is validated before cmd/go starts. Gograph also reads project metadata such as .gitignore, graph/config JSON, and Git state. Indexing asks the installed Go toolchain for the effective build/module context; precise mode additionally performs package type loading, and doc runs go doc. Those operations follow your configured module/cache/network policy. Before repository package loading or go doc, applicable local module/workspace source trees are preflighted for links that cmd/go may inspect; .git and .gograph subtrees are excluded. Session telemetry is local under .gograph/sessions/; nothing is sent to gograph services.

Quick Start

# Install
brew install --cask ozgurcd/tap/gograph
# or: go install github.com/ozgurcd/gograph/cmd/gograph@latest

# Confirm which installation will run and detect PATH shadowing
gograph doctor --json

# Build a type-enriched precise graph, then verify it
gograph build . --precise
gograph stats

# Start with repository-wide results that require no guessed symbol
gograph summary
gograph hotspot --top 5
gograph flow --no-tests

Homebrew and go install install the normal gograph CLI. MCP clients that support MCP Bundles can instead discover the local stdio server in the official MCP Registry as io.github.ozgurcd/gograph. Registry/MCPB installation is a separate distribution path; it does not install the Homebrew cask or configure the Claude Code marketplace plugin. The Registry is currently in preview. See Official MCP Registry and MCPB installation for client support, target selection, and current limitations.

Choose a real function or method shown by summary, hotspot, or gograph complexity, then substitute its name below:

gograph context "YourSymbol" # source + callers + callees + tests

# For compilable repositories, enrich the graph before a major refactor
gograph build . --precise
gograph plan "YourSymbol"

Build artifacts are written under the target .gograph/ directory. gograph adds .gograph/ to the enclosing Git repository root .gitignore when available, falls back to the build target .gitignore outside Git, and exits without replacing artifacts if no Go files are found or no source file parses successfully. The update accepts only an absent or regular .gitignore; a repository-provided link is refused and its target is not modified. Go build constraints, cmd/go package-directory rules, generated sources, module-mode ignore directives, and Git ignores use the same scanner policy for building, freshness checks, and change detection. Source-file symlinks and other non-regular .go entries are reported and excluded; linked/non-regular go.mod, go.sum, go.work, go.work.sum, and vendor/modules.txt entries are rejected before gograph or the Go toolchain reads them. Applicable go.work use members must remain beneath the workspace directory; their directories, go.mod, and optional go.sum are validated before cmd/go starts. .gograph itself must be a real directory, and graph.json must be a regular repository-confined file. Graphs with a missing or unsupported confinement policy marker must be rebuilt with the current binary before graph-backed commands use them. Older binaries do not enforce this boundary and should not be used to analyze untrusted repositories.

Each indexed source file stores a SHA-256 content digest. Rebuilds reparse all selected files in a changed package together and reuse parser records for unchanged packages; stats reports reused_files and rebuilt_packages. Precise builds reuse that AST work but still recompute repository-wide type/CHA/SSA enrichment so cross-package dispatch remains correct.

Machine-readable structural validation

External consumers can validate one closed structural predicate without parsing human CLI output:

gograph version --json
gograph validate --repo /work/project --binding-json '{"schema_version":"gograph.binding.v1","predicate":"symbol_exists","subject":{"language":"go","kind":"symbol","id":"example.com/project/internal/auth::Authorize"},"required_precision":"ast"}' --json

The version and result schemas are gograph.version.v1 and gograph.validation.v1; bindings use gograph.binding.v1. V1 supports only symbol_exists, package_imports, call_edge_exists, and type_implements. Validation is read-only and never builds or refreshes the graph. Exit 0 means pass, exit 1 means a conclusively evaluated fail, and exit 2 means cannot_evaluate or an invalid request.

Negative results require predicate-specific completeness: symbol and direct import absence need a current complete AST graph; implementation absence needs a current precise-complete graph; call absence additionally requires complete resolution of the subject's relevant call edges. Missing, stale, partial, ambiguous, or unresolved evidence degrades to cannot_evaluate; a precise_fallback graph may support AST presence but never evaluated absence. The result binds the exact graph bytes, selected source/build-context manifest, and canonical binding with SHA-256 fingerprints.

Gograph validates selected-build-context Go structure. It does not prove runtime behavior or business correctness. CHA edges are possible static targets, not runtime dispatch certainty. V1 excludes reachability, unstable or external symbol identities, unnamed types, and non-Go languages. See the exact machine-validation contract. Applicable local module/workspace source roots must remain beneath the explicit --repo root; v1 returns cannot_evaluate instead of widening that authority.

MCP refreshes stay in memory by default. To publish each successful refresh for CLI consumers and later server processes, start the server explicitly with:

gograph mcp . --persist-refresh

This opt-in mode writes or overwrites .gograph/graph.json and the nine Markdown reports after a confirmed-fresh refresh. It does not modify .gitignore, so ignore .gograph/ yourself before enabling it when needed. The directory holds only the latest published state; it is not a per-branch cache. If no usable graph exists (including an unsafe or unsupported artifact), the startup auto-build is published before serving; a failure there prevents startup. A later tool-triggered publication failure makes that tool return an error, and the server retries the pending publication on another refresh-capable call without rebuilding the already-fresh in-memory graph. Writers coordinate through a local .gograph/.artifacts.lock file; an existing lock entry must be regular rather than a link or special file. Reports are replaced first and graph.json is replaced last as the publication commit marker; the complete ten-file bundle is not a single atomic filesystem transaction. Same-directory replacement is atomic on Unix-like systems; Go does not guarantee atomic rename semantics on non-Unix platforms. The lock file remains as operational coordination state in addition to the ten outputs.

Why gograph?

Illustrative point-in-time output comparison from an earlier gograph revision (counts vary as the repository evolves; these commands return different kinds of evidence):

Taskgrep -rngographObserved output difference
Find callers of loadGraph158 matching lines (comments, docs, vars)56 AST-derived call-site rows~65% fewer rows in that run
Locate symbol definitions842 lines matching "Symbol"83 true type/method declarations~90% noise eliminated
Read one function bodycat displays 180+ lines of the whole filesource extracts the 12-line function~93% fewer source lines in that run
Gather common symbol contextSeparate node, source, caller, callee, and test queriescontext bundles those fieldsFive evidence types in one response

Key Features

Machine and Agent Workflows — callers, callees, reverse test coverage, stable symbol identity, impact, context, plan, review, flow, errorflow, structural validation, orphans, hotspot, coupling, and more. The MCP server registers 67 endpoints including four session lifecycle tools. Full command reference →

Federated Workspaces — model multiple checked-out repositories through independently fingerprinted repository graphs plus a small deterministic cross-repository overlay. Resolution scopes support alternative fleets such as OSS/CE without merging repository ownership. P0 resolves Go modules, ordinary cross-repository Go calls, and first-class HTTP contracts for workspace-wide status, query, path, and impact analysis. The four read-only workspace MCP tools return the same native result values as CLI --json; member refresh and overlay publication remain explicit CLI mutations. Workspace guide →

Native MCP Server — all 63 repository query, analysis, and workflow capabilities have project-MCP equivalents for Claude, Cursor, Copilot, and other MCP clients; four additional endpoints cover session lifecycle (67 project tools total). A separate workspace server provides status, query, path, and impact with the same native results as the corresponding CLI operations. The normal mapping is CLI <command> to MCP gograph_<command>; contract, boundaries --create, and session actions use the documented special mappings. CLI-only process/host/artifact operations are build, validate, doctor, gate, snapshot, plugin/hook installation, project/workspace MCP startup, workspace build

View source on GitHub