diff --git a/packages/opencode/test/mcp/config.test.ts b/packages/opencode/test/mcp/config.test.ts
new file mode 100644
index 0000000000..4a958c2b78
--- /dev/null
+++ b/packages/opencode/test/mcp/config.test.ts
@@ -0,0 +1,166 @@
+import { describe, test, expect } from "bun:test"
+import { tmpdir } from "../fixture/fixture"
+import { mkdir, writeFile, readFile } from "fs/promises"
+import path from "path"
+import {
+  resolveConfigPath,
+  addMcpToConfig,
+  removeMcpFromConfig,
+  listMcpInConfig,
+  findAllConfigPaths,
+} from "../../src/mcp/config"
+
+describe("MCP config: resolveConfigPath", () => {
+  test("returns .altimate-code subdir config when it exists", async () => {
+    await using tmp = await tmpdir()
+    const configDir = path.join(tmp.path, ".altimate-code")
+    await mkdir(configDir, { recursive: true })
+    await writeFile(path.join(configDir, "altimate-code.json"), "{}")
+    const result = await resolveConfigPath(tmp.path)
+    expect(result).toBe(path.join(configDir, "altimate-code.json"))
+  })
+
+  test("prefers .altimate-code over .opencode subdir", async () => {
+    await using tmp = await tmpdir()
+    await mkdir(path.join(tmp.path, ".altimate-code"), { recursive: true })
+    await writeFile(path.join(tmp.path, ".altimate-code", "altimate-code.json"), "{}")
+    await mkdir(path.join(tmp.path, ".opencode"), { recursive: true })
+    await writeFile(path.join(tmp.path, ".opencode", "opencode.json"), "{}")
+    const result = await resolveConfigPath(tmp.path)
+    expect(result).toBe(path.join(tmp.path, ".altimate-code", "altimate-code.json"))
+  })
+
+  test("falls back to root-level config", async () => {
+    await using tmp = await tmpdir()
+    await writeFile(path.join(tmp.path, "opencode.json"), "{}")
+    const result = await resolveConfigPath(tmp.path)
+    expect(result).toBe(path.join(tmp.path, "opencode.json"))
+  })
+
+  test("returns first candidate path when no config exists", async () => {
+    await using tmp = await tmpdir()
+    const result = await resolveConfigPath(tmp.path)
+    expect(result).toBe(path.join(tmp.path, ".altimate-code", "altimate-code.json"))
+  })
+
+  test("global=true skips subdirectory configs", async () => {
+    await using tmp = await tmpdir()
+    await mkdir(path.join(tmp.path, ".altimate-code"), { recursive: true })
+    await writeFile(path.join(tmp.path, ".altimate-code", "altimate-code.json"), "{}")
+    await writeFile(path.join(tmp.path, "opencode.json"), "{}")
+    const result = await resolveConfigPath(tmp.path, true)
+    expect(result).toBe(path.join(tmp.path, "opencode.json"))
+  })
+})
+
+describe("MCP config: addMcpToConfig + removeMcpFromConfig round-trip", () => {
+  test("adds MCP server to empty config", async () => {
+    await using tmp = await tmpdir()
+    const configPath = path.join(tmp.path, "opencode.json")
+    await addMcpToConfig("test-server", { type: "local", command: ["node", "server.js"] } as any, configPath)
+    const content = JSON.parse(await readFile(configPath, "utf-8"))
+    expect(content.mcp["test-server"]).toMatchObject({ type: "local", command: ["node", "server.js"] })
+  })
+
+  test("adds MCP server to existing config preserving other fields", async () => {
+    await using tmp = await tmpdir()
+    const configPath = path.join(tmp.path, "opencode.json")
+    await writeFile(configPath, JSON.stringify({ provider: { default: "anthropic" } }))
+    await addMcpToConfig("my-server", { type: "remote", url: "https://example.com" } as any, configPath)
+    const content = JSON.parse(await readFile(configPath, "utf-8"))
+    expect(content.provider.default).toBe("anthropic")
+    expect(content.mcp["my-server"].url).toBe("https://example.com")
+  })
+
+  test("remove returns false for nonexistent config file", async () => {
+    await using tmp = await tmpdir()
+    const result = await removeMcpFromConfig("nope", path.join(tmp.path, "missing.json"))
+    expect(result).toBe(false)
+  })
+
+  test("remove returns false for nonexistent server name", async () => {
+    await using tmp = await tmpdir()
+    const configPath = path.join(tmp.path, "opencode.json")
+    await writeFile(configPath, JSON.stringify({ mcp: { existing: { type: "local", command: ["x"] } } }))
+    const result = await removeMcpFromConfig("nonexistent", configPath)
+    expect(result).toBe(false)
+  })
+
+  test("add then remove round-trips correctly", async () => {
+    await using tmp = await tmpdir()
+    const configPath = path.join(tmp.path, "opencode.json")
+    await addMcpToConfig("ephemeral", { type: "local", command: ["test"] } as any, configPath)
+    const listed = await listMcpInConfig(configPath)
+    expect(listed).toContain("ephemeral")
+    const removed = await removeMcpFromConfig("ephemeral", configPath)
+    expect(removed).toBe(true)
+    const after = await listMcpInConfig(configPath)
+    expect(after).not.toContain("ephemeral")
+  })
+})
+
+describe("MCP config: listMcpInConfig", () => {
+  test("returns empty array for missing file", async () => {
+    await using tmp = await tmpdir()
+    const result = await listMcpInConfig(path.join(tmp.path, "nope.json"))
+    expect(result).toEqual([])
+  })
+
+  test("returns empty array for config without mcp key", async () => {
+    await using tmp = await tmpdir()
+    const configPath = path.join(tmp.path, "opencode.json")
+    await writeFile(configPath, JSON.stringify({ provider: {} }))
+    const result = await listMcpInConfig(configPath)
+    expect(result).toEqual([])
+  })
+
+  test("lists all server names", async () => {
+    await using tmp = await tmpdir()
+    const configPath = path.join(tmp.path, "opencode.json")
+    await writeFile(
+      configPath,
+      JSON.stringify({
+        mcp: {
+          alpha: { type: "local", command: ["a"] },
+          beta: { type: "remote", url: "https://b.com" },
+        },
+      }),
+    )
+    const result = await listMcpInConfig(configPath)
+    expect(result).toEqual(expect.arrayContaining(["alpha", "beta"]))
+    expect(result).toHaveLength(2)
+  })
+})
+
+describe("MCP config: findAllConfigPaths", () => {
+  test("returns paths from both project and global dirs", async () => {
+    await using projTmp = await tmpdir()
+    await using globalTmp = await tmpdir()
+    await writeFile(path.join(projTmp.path, "opencode.json"), "{}")
+    await writeFile(path.join(globalTmp.path, "altimate-code.json"), "{}")
+    const result = await findAllConfigPaths(projTmp.path, globalTmp.path)
+    expect(result).toContain(path.join(projTmp.path, "opencode.json"))
+    expect(result).toContain(path.join(globalTmp.path, "altimate-code.json"))
+  })
+
+  test("includes project subdirs but not global subdirs", async () => {
+    await using projTmp = await tmpdir()
+    await using globalTmp = await tmpdir()
+    // Create config in project .opencode subdir
+    await mkdir(path.join(projTmp.path, ".opencode"), { recursive: true })
+    await writeFile(path.join(projTmp.path, ".opencode", "opencode.json"), "{}")
+    // Create config in global .opencode subdir (should NOT be found)
+    await mkdir(path.join(globalTmp.path, ".opencode"), { recursive: true })
+    await writeFile(path.join(globalTmp.path, ".opencode", "opencode.json"), "{}")
+    const result = await findAllConfigPaths(projTmp.path, globalTmp.path)
+    expect(result).toContain(path.join(projTmp.path, ".opencode", "opencode.json"))
+    expect(result).not.toContain(path.join(globalTmp.path, ".opencode", "opencode.json"))
+  })
+
+  test("returns empty when no config files exist", async () => {
+    await using projTmp = await tmpdir()
+    await using globalTmp = await tmpdir()
+    const result = await findAllConfigPaths(projTmp.path, globalTmp.path)
+    expect(result).toEqual([])
+  })
+})
diff --git a/packages/opencode/test/util/locale.test.ts b/packages/opencode/test/util/locale.test.ts
new file mode 100644
index 0000000000..9a0791983f
--- /dev/null
+++ b/packages/opencode/test/util/locale.test.ts
@@ -0,0 +1,81 @@
+import { describe, test, expect } from "bun:test"
+import { Locale } from "../../src/util/locale"
+
+describe("Locale.number", () => {
+  test("formats millions", () => {
+    expect(Locale.number(1500000)).toBe("1.5M")
+    expect(Locale.number(1000000)).toBe("1.0M")
+  })
+
+  test("formats thousands", () => {
+    expect(Locale.number(1500)).toBe("1.5K")
+    expect(Locale.number(1000)).toBe("1.0K")
+  })
+
+  test("boundary: 999999 renders as K not M", () => {
+    expect(Locale.number(999999)).toBe("1000.0K")
+  })
+
+  test("returns raw string for small numbers", () => {
+    expect(Locale.number(999)).toBe("999")
+    expect(Locale.number(0)).toBe("0")
+  })
+})
+
+describe("Locale.duration", () => {
+  test("milliseconds", () => {
+    expect(Locale.duration(500)).toBe("500ms")
+    expect(Locale.duration(0)).toBe("0ms")
+  })
+
+  test("seconds", () => {
+    expect(Locale.duration(1500)).toBe("1.5s")
+    expect(Locale.duration(2500)).toBe("2.5s")
+  })
+
+  test("minutes and seconds", () => {
+    expect(Locale.duration(90000)).toBe("1m 30s")
+    expect(Locale.duration(3599999)).toBe("59m 59s")
+  })
+
+  test("hours and minutes", () => {
+    expect(Locale.duration(3600000)).toBe("1h 0m")
+    expect(Locale.duration(5400000)).toBe("1h 30m")
+  })
+
+  // BUG: Locale.duration >=24h has swapped days/hours calculation.
+  // hours = Math.floor(input / 3600000) gives total hours (25), not remainder.
+  // days = Math.floor((input % 3600000) / 86400000) always yields 0.
+  // Correct: days = Math.floor(input / 86400000), hours = Math.floor((input % 86400000) / 3600000)
+  // 90000000ms = 25h = 1d 1h — should display "1d 1h"
+  // See: https://github.com/AltimateAI/altimate-code/issues/368
+  test.skip("FIXME: days and hours for >=24h are calculated correctly", () => {
+    expect(Locale.duration(90000000)).toBe("1d 1h")
+  })
+})
+
+describe("Locale.truncateMiddle", () => {
+  test("returns original if short enough", () => {
+    expect(Locale.truncateMiddle("hello", 35)).toBe("hello")
+  })
+
+  test("truncates long strings with ellipsis in middle", () => {
+    const long = "abcdefghijklmnopqrstuvwxyz1234567890abcdef"
+    const result = Locale.truncateMiddle(long, 20)
+    expect(result.length).toBe(20)
+    expect(result).toContain("\u2026")
+    expect(result.startsWith("abcdefghij")).toBe(true)
+    expect(result.endsWith("bcdef")).toBe(true)
+  })
+})
+
+describe("Locale.pluralize", () => {
+  test("uses singular for count=1", () => {
+    expect(Locale.pluralize(1, "{} item", "{} items")).toBe("1 item")
+  })
+
+  test("uses plural for count!=1", () => {
+    expect(Locale.pluralize(0, "{} item", "{} items")).toBe("0 items")
+    expect(Locale.pluralize(5, "{} item", "{} items")).toBe("5 items")
+  })
+})