flowchart TD
    subgraph client["MCP client — Claude Desktop / Cursor"]
        A["Agent (the LLM)"]
    end

    subgraph server["apollo-cache-copilot (stdio process)"]
        T["StdioServerTransport<br/>apollo-copilot mcp"]
        R["Tool registry<br/>inspect_dangling_refs<br/>patch_cache<br/>diagnose_cache_graph"]
        Z["Zod schemas<br/>parse in, shape out"]

        subgraph g["cacheAgentGraph (LangGraph, LLM-free)"]
            I["inspectorNode<br/>writes findings"]
            RE["reasonerNode<br/>writes proposedPatches"]
            P["patcherNode<br/>writes narration"]
            I --> RE --> P
        end

        TOOL1["inspectDanglingRefs()<br/>pure, on a snapshot"]
        TOOL2["patchCache()<br/>modify / evict / gc"]

        T --> R --> Z --> I
        I -.->|calls| TOOL1
        P -.->|plans for| TOOL2
    end

    A <-->|"JSON-RPC 2.0 over stdio"| T
    TOOL1 --- CACHE["cache.extract() snapshot"]
    TOOL2 --- LIVE["live ApolloCache"]

  MCP client (Claude Desktop, Cursor, any stdio client)
        │  JSON-RPC 2.0  ▲
        ▼   over stdio   │  stdout IS the protocol channel —
  ┌─────────────────────────────────┐   all logs go to stderr
  │ StdioServerTransport            │
  ├─────────────────────────────────┤
  │ tools: inspect_dangling_refs    │  read-only
  │        patch_cache              │  mutating (dryRun available)
  │        diagnose_cache_graph     │  read-only, plans only
  ├─────────────────────────────────┤
  │ Zod schemas — parse at the edge │
  └───────────────┬─────────────────┘
                  ▼
  ┌─────────────────────────────────────────────────────┐
  │  cacheAgentGraph  (LangGraph, deliberately LLM-free)│
  │                                                     │
  │  INSPECTOR ──────► REASONER ──────► PATCHER         │
  │  walks the store   maps findings    narrates the     │
  │  → findings[]      → patch ops      plan             │
  │      │                  │                            │
  │      │ owns `findings`  │ owns `proposedPatches`      │
  └──────┼──────────────────┼────────────────────────────┘
         ▼                  ▼
  inspectDanglingRefs()   patchCache()
  pure, on a snapshot     cache.modify / evict / gc on a live cache

npm install @indianic/apollo-cache-copilot
# or, from a checkout
npm install && npm run build

import { inspectDanglingRefs } from 'apollo-cache-copilot';

const { findings, stats } = inspectDanglingRefs({
  cache: client.cache.extract(),
  // all optional:
  rootIds: ['ROOT_QUERY', 'ROOT_MUTATION'], // reachability roots
  includeUnreachable: true,                  // report gc candidates
  includeNormalizationGaps: true,            // report un-keyable inline objects
});

console.log(stats);
// { entityCount: 4, refCount: 3, danglingCount: 1, unreachableCount: 1 }

for (const f of findings) {
  console.log(f.kind, f.path, f.danglingRef ?? '');
  // ORPHANED_REF  User:1.avatar  Avatar:99
  // UNREACHABLE_ENTITY  Post:7
}

import { patchCache } from 'apollo-cache-copilot';

const { dryRun, results, collected } = patchCache(client.cache, {
  operations: [
    // drop dangling refs from a list field
    { type: 'modify', id: 'User:1', fields: { posts: { action: 'PRUNE_DANGLING_REFS' } } },
    // delete / invalidate / overwrite a field
    { type: 'modify', id: 'User:1', fields: { avatar: { action: 'DELETE' } } },
    { type: 'modify', id: 'User:1', fields: { bio: { action: 'SET', value: 'unset' } } },
    // evict an entity, or one field of it
    { type: 'evict', id: 'Post:7' },
    { type: 'evict', id: 'ROOT_QUERY', fieldName: 'user', args: { id: '1' } },
  ],
  gc: true,       // run cache.gc() once, after everything lands
  dryRun: false,  // true = validate only, cache untouched
});

results.forEach((r) => console.log(r.changed, r.error ?? ''));
console.log('collected:', collected); // keys gc() removed

import { cacheAgentGraph } from 'apollo-cache-copilot';

const state = await cacheAgentGraph.invoke({ cacheState: client.cache.extract() });

state.messages.forEach((m) => console.log(String(m.content)));
// 2 findings: 1 orphaned ref, 1 unreachable entity.
// ...

// Review, then apply:
patchCache(client.cache, { operations: state.proposedPatches });

apollo-copilot [mcp]          Start the stdio MCP server (default when no args)
apollo-copilot inspect FILE   Diagnose a JSON cache snapshot and print findings

// in the RN app
console.log(JSON.stringify(client.cache.extract()));

npx -y -p @indianic/apollo-cache-copilot apollo-copilot inspect ./cache-snapshot.json

━━ Cache Diagnostic ━━

Entities: 4 | Refs: 3 | Dangling: 1 | Unreachable: 1

⚠  ORPHANED_REF (1)
   • User:1.avatar → Avatar:99
     Points at "Avatar:99", which is not in the cache. Reads here return undefined.

🗑  UNREACHABLE_ENTITY (1)
   • Post:7
     No root reaches this entity; cache.gc() would collect it.

{
  "mcpServers": {
    "apollo-cache-copilot": {
      "command": "npx",
      "args": ["-y", "-p", "@indianic/apollo-cache-copilot", "apollo-copilot", "mcp"]
    }
  }
}

{
  "mcpServers": {
    "apollo-cache-copilot": {
      "command": "node",
      "args": ["/absolute/path/to/apollo-cache-copilot/bin/apollo-copilot.js", "mcp"]
    }
  }
}

{
  "mcpServers": {
    "apollo-cache-copilot": {
      "command": "npx",
      "args": ["-y", "-p", "@indianic/apollo-cache-copilot", "apollo-copilot", "mcp"]
    }
  }
}

{
  "mcpServers": {
    "apollo-cache-copilot": {
      "command": "node",
      "args": ["${workspaceFolder}/bin/apollo-copilot.js", "mcp"]
    }
  }
}

npm install
npm run build      # tsc -> dist/  (run first: typecheck and tests import dist)
npm run typecheck  # tsc --noEmit -p tsconfig.test.json (includes tests)
npm test           # vitest run