# Devin Desktop edits the file. Maguyva sees the repo. Canonical source: https://maguyva.ai/for-windsurf License: text under [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/); code samples under [MIT-0](https://opensource.org/license/mit-0); the Maguyva name, logos, brand assets and other code are not covered. Details: [maguyva.ai/license](https://maguyva.ai/license). Devin Desktop (the Windsurf IDE) is the editor and Devin Local is the agent. In a monorepo, the agent still needs a map of which file matters. Maguyva indexes your codebase and serves it back over MCP (semantic, AST, graph, and text), so “where does auth happen” returns the actual auth flow, not seven test stubs. > Devin Desktop edits what you point at. Maguyva tells Devin Local which file to point at. ## What each layer does Four pieces. Each one has a job. ### Devin Desktop Where you and Devin Local actually work. ### @ mentions + .devin/rules/ Manual context wins, until the repo is big. ### Maguyva Automatic codebase facts over MCP. ### Workspaces, not seats Agents don’t pay seats. [See pricing](https://maguyva.ai/pricing) ## Devin Desktop is the editor. Use it. The IDE is not the problem. Devin Local, tab completion, multi-file edits, and `.devin/rules/` are excellent, and you already use them for: - Inline suggestions and Devin Local edits in the open file. - Multi-file edits when the change is local. - `.devin/rules/` for repo conventions and style guardrails. - `@`-mentions to pull a specific file into context. Keep doing that. None of it goes away. But in a real monorepo (TypeScript with workspace deps, Python services, mixed packages) agent context breaks the moment the relevant file isn’t already on Devin Local’s radar. ## Manual fixes you’ve already tried, and where they break Four manual fixes paired with their failure mode. Left = what you do today. Right = where it breaks. ### // mention the files You `@`-mention the three files you think matter. Devin Local edits cleanly inside them. ### // mentioning is a guess It works when you already know which files are involved. The whole point of context tools is to surface the files you didn’t know to mention. ### // paste the snippets You paste 200 lines from another package into Devin Local to give it enough context. ### // pasted code goes stale The snippet you pasted at 9 a.m. doesn’t reflect the rebase your teammate landed at 11 a.m. Devin Local is editing against a phantom version of the package. ### // write a context doc You write a `.devin/rules/` file or an architecture markdown. It’s right today. ### // docs drift faster than code Anything you write by hand drifts. The code is the source of truth. A doc explaining the queue layer is correct for a week, then wrong forever. ### // keep the rules files You add `.devin/rules/` for naming, lint, and build commands. Great for behavior. ### // rules ≠ index `.devin/rules/` is the right place for “always run pnpm tsc -b before commits.” It is not a queryable index of every symbol, file, and call-site in your monorepo. ## Maguyva is the layer underneath Not a Devin Desktop replacement. The repo-context layer that hangs off Devin Local’s MCP support. - **Semantic + AST + graph + text**: search by meaning, structure, dependency, or literal. Every hit returns a file path and line number. - **Cross-package by default**: call-sites and importers across every package in the monorepo, not just the one Devin Local has open. - **Branch-aware**: Maguyva sees the version of the code Devin Local is editing. - **Complementary, not competitive**: `.devin/rules/` keeps doing its job. `@`-mentions keep doing theirs. Maguyva fills the gap they don’t fill. > Devin Local edits the file you point at. > Maguyva tells the agent *which file to point at.* ## Three monorepo workflows Cross-package, cross-language. Grounded against the actual call graph, not Devin Local’s grep. ### 01. Find the auth flow across packages, without mentioning anything ```text devin> where does authentication happen in this monorepo? graph::query("authentication flow") packages/web/src/auth/session.ts:42 middleware packages/api/src/auth/jwt.ts:88 token verify packages/shared/src/auth/types.ts:12 AuthContext packages/admin/src/auth/admin-only.ts:31 rbac gate → 4 entry points across 4 packages, ranked by call-site density. [exit 0] ``` You didn’t mention a file. You didn’t paste a snippet. Devin Local has the four files that matter, in the right ranking, and can make a grounded edit. ### 02. Find the real implementation, not the test stub ```text devin> how does normalizePhoneNumber handle E.164? semantic::query("normalize phone E.164") packages/shared/util/phone.ts:88 normalizePhoneNumber() ← real impl packages/api/test/phone.spec.ts:14 jest.mock(...) ← stub [exit 0] ``` Names lie. Mocks shadow real code. Maguyva ranks the real implementation above the test mock, across every package. ### 03. Check blast radius before you refactor ```text devin> what calls QueueDispatcher.publish across the monorepo? graph::callers(QueueDispatcher.publish) 3 in packages/billing/* 1 in packages/audit/* 1 in packages/notifications/* 1 in services/python-worker/* ← cross-language via gRPC stub [exit 0] ``` Cross-package, and cross-language when you have a polyglot repo, call-sites surface inline. The diff is grounded against real importers, not Devin Local’s grep. ## Setup with Devin Desktop Three steps. Free tier: 3 repos, 50K indexed lines, no card. ### 01. Index a repo at maguyva.ai Pick the monorepo where you’ve felt the most context pain. ### 02. Add Maguyva as an MCP server in Devin Desktop `~/.config/devin/mcp_config.json` ```json { "mcpServers": { "maguyva": { "url": "https://maguyva.tools/mcp", "headers": { "Authorization": "Bearer ${env:MAGUYVA_API_KEY}" } } } } ``` ### 03. Ask one question whose answer you already know Don’t start with your whole company. Start with one repo and one verifiable question, like “what calls `formatInvoice` across packages?” ## Index one repo you already know. Test one question whose answer you can verify.