diff --git a/README.md b/README.md
index 93b7b262c..4e5789e89 100644
--- a/README.md
+++ b/README.md
@@ -189,6 +189,11 @@ sources are merged; on a name collision `reasonix.toml` wins.
 }
 ```
 
+**Upgrading from `0.x`?** Your old `~/.reasonix/config.json` is still read for its
+`mcpServers` (honouring `mcpDisabled`) as a lowest-priority source, so MCP servers
+keep working — move them into `reasonix.toml`'s `[[plugins]]` or a `.mcp.json` when
+convenient.
+
 ### Slash commands
 
 In `reasonix chat`, built-in commands (`/compact`, `/new`, `/rewind`, `/tree`,
diff --git a/README.zh-CN.md b/README.zh-CN.md
index a3171b928..242121669 100644
--- a/README.zh-CN.md
+++ b/README.zh-CN.md
@@ -178,6 +178,10 @@ headers = { Authorization = "Bearer ${STRIPE_KEY}" }
 }
 ```
 
+**从 `0.x` 升级？** 旧的 `~/.reasonix/config.json` 仍会被读取(读其 `mcpServers`、并遵从
+`mcpDisabled`),作为最低优先级来源——所以 MCP 服务器照常可用;方便时再把它们挪进
+`reasonix.toml` 的 `[[plugins]]` 或 `.mcp.json`。
+
 ### 斜杠命令
 
 `reasonix chat` 里,内置命令(`/compact`、`/new`、`/rewind`、`/tree`、`/branch`、`/switch`、`/todo`、`/model`、`/effort`、`/mcp`、`/help`)在本地执行。
diff --git a/internal/config/config.go b/internal/config/config.go
index 7e2a12c80..2032b5037 100644
--- a/internal/config/config.go
+++ b/internal/config/config.go
@@ -490,8 +490,9 @@ func Default() *Config {
 }
 
 // Load builds the configuration: defaults, then user config, then project
-// config, then any MCP servers from Claude Code's .mcp.json. A .env in the
-// working directory is loaded first so api_key_env can resolve.
+// config, then MCP servers from Claude Code's .mcp.json, then (lowest priority)
+// the v0.x ~/.reasonix/config.json's mcpServers. A .env in the working directory
+// is loaded first so api_key_env can resolve.
 func Load() (*Config, error) {
 	loadDotEnv()
 	cfg := Default()
@@ -523,6 +524,11 @@ func Load() (*Config, error) {
 		return nil, err
 	}
 	cfg.mergeMCPJSON(entries)
+
+	// Lowest priority: the v0.x ~/.reasonix/config.json's mcpServers, so upgrading
+	// from the TypeScript line keeps MCP servers without rewriting them. Anything
+	// the v2 config or .mcp.json already declared wins on a name collision.
+	cfg.mergeMCPJSON(loadLegacyMCP(legacyConfigPath()))
 	normalizeLegacyEffort(cfg)
 	return cfg, nil
 }
diff --git a/internal/config/mcpjson.go b/internal/config/mcpjson.go
index af516c37d..934a64bb0 100644
--- a/internal/config/mcpjson.go
+++ b/internal/config/mcpjson.go
@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"os"
+	"path/filepath"
 	"sort"
 )
 
@@ -43,14 +44,23 @@ func loadMCPJSON(path string) ([]PluginEntry, error) {
 	if err := json.Unmarshal(b, &doc); err != nil {
 		return nil, fmt.Errorf("mcp config %s: %w", path, err)
 	}
-	names := make([]string, 0, len(doc.MCPServers))
-	for name := range doc.MCPServers {
-		names = append(names, name)
+	return specsToEntries(doc.MCPServers, nil), nil
+}
+
+// specsToEntries converts an mcpServers map to PluginEntry values, sorted by name
+// for a stable connection order. Names in skip are dropped (used for v0.x's
+// mcpDisabled list).
+func specsToEntries(specs map[string]mcpServerSpec, skip map[string]bool) []PluginEntry {
+	names := make([]string, 0, len(specs))
+	for name := range specs {
+		if !skip[name] {
+			names = append(names, name)
+		}
 	}
 	sort.Strings(names)
 	entries := make([]PluginEntry, 0, len(names))
 	for _, name := range names {
-		s := doc.MCPServers[name]
+		s := specs[name]
 		entries = append(entries, PluginEntry{
 			Name:      name,
 			Type:      s.Type,
@@ -62,7 +72,44 @@ func loadMCPJSON(path string) ([]PluginEntry, error) {
 			AutoStart: s.AutoStart,
 		})
 	}
-	return entries, nil
+	return entries
+}
+
+// legacyConfigPath is the v0.x (TypeScript line) config file, ~/.reasonix/config.json.
+func legacyConfigPath() string {
+	home, err := os.UserHomeDir()
+	if err != nil {
+		return ""
+	}
+	return filepath.Join(home, ".reasonix", "config.json")
+}
+
+// loadLegacyMCP reads the v0.x ~/.reasonix/config.json and returns its enabled
+// mcpServers as PluginEntry values (servers listed in its mcpDisabled are
+// skipped), so upgrading from v0.x keeps MCP servers working without rewriting
+// them as [[plugins]]. Absent or malformed → nil: a stale legacy file must never
+// block startup, and it is the lowest-priority source anyway (the v2 config and
+// .mcp.json win on a name collision — see Load).
+func loadLegacyMCP(path string) []PluginEntry {
+	if path == "" {
+		return nil
+	}
+	b, err := os.ReadFile(path)
+	if err != nil {
+		return nil
+	}
+	var doc struct {
+		MCPServers  map[string]mcpServerSpec `json:"mcpServers"`
+		MCPDisabled []string                 `json:"mcpDisabled"`
+	}
+	if err := json.Unmarshal(b, &doc); err != nil {
+		return nil
+	}
+	disabled := make(map[string]bool, len(doc.MCPDisabled))
+	for _, n := range doc.MCPDisabled {
+		disabled[n] = true
+	}
+	return specsToEntries(doc.MCPServers, disabled)
 }
 
 // mergeMCPJSON appends servers from .mcp.json that the TOML config did not
diff --git a/internal/config/mcpjson_test.go b/internal/config/mcpjson_test.go
index f3c31c75d..7bf15369c 100644
--- a/internal/config/mcpjson_test.go
+++ b/internal/config/mcpjson_test.go
@@ -166,3 +166,50 @@ func TestMergeMCPJSONPrecedence(t *testing.T) {
 		t.Errorf("non-colliding entry not appended: %+v", cfg.Plugins[1])
 	}
 }
+
+func TestLoadLegacyMCP(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "config.json")
+	doc := `{
+  "mcpServers": {
+    "github":  { "command": "npx", "args": ["-y", "server-github"], "env": { "TOKEN": "x" } },
+    "old":     { "command": "foo" },
+    "remote":  { "type": "sse", "url": "https://x/sse", "headers": { "Authorization": "Bearer y" } }
+  },
+  "mcpDisabled": ["old"],
+  "projects": { "/some/root": { "shellAllowed": [] } }
+}`
+	if err := os.WriteFile(path, []byte(doc), 0o644); err != nil {
+		t.Fatal(err)
+	}
+
+	got := loadLegacyMCP(path)
+	// "old" is in mcpDisabled and dropped; github + remote remain, name-sorted.
+	if len(got) != 2 {
+		t.Fatalf("got %d entries, want 2: %+v", len(got), got)
+	}
+	if got[0].Name != "github" || got[1].Name != "remote" {
+		t.Fatalf("names = %q, %q; want github, remote", got[0].Name, got[1].Name)
+	}
+	if got[0].Command != "npx" || got[0].Env["TOKEN"] != "x" {
+		t.Errorf("github mapped wrong: %+v", got[0])
+	}
+	if got[1].Type != "sse" || got[1].URL != "https://x/sse" || got[1].Headers["Authorization"] != "Bearer y" {
+		t.Errorf("remote mapped wrong: %+v", got[1])
+	}
+
+	// Absent, malformed, and empty paths must not error — just yield nil, so a
+	// stale legacy file can never block startup.
+	if got := loadLegacyMCP(filepath.Join(dir, "nope.json")); got != nil {
+		t.Errorf("absent file: got %+v, want nil", got)
+	}
+	if err := os.WriteFile(path, []byte("{not json"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	if got := loadLegacyMCP(path); got != nil {
+		t.Errorf("malformed file: got %+v, want nil", got)
+	}
+	if got := loadLegacyMCP(""); got != nil {
+		t.Errorf("empty path: got %+v, want nil", got)
+	}
+}