diff --git a/.changeset/update-known-models.md b/.changeset/update-known-models.md
new file mode 100644
index 00000000..f56c3031
--- /dev/null
+++ b/.changeset/update-known-models.md
@@ -0,0 +1,5 @@
+---
+"@perstack/core": patch
+---
+
+Add latest models to known-models: claude-opus-4-6, gpt-5.1, gpt-5.2, gpt-5.2-pro, gemini-3-flash-preview
diff --git a/e2e/experts/bundled-base.toml b/e2e/experts/bundled-base.toml
index 4621717a..d4cf2336 100644
--- a/e2e/experts/bundled-base.toml
+++ b/e2e/experts/bundled-base.toml
@@ -1,7 +1,7 @@
 # E2E test configuration for bundled base skill with InMemoryTransport
 # Tests that the bundled @perstack/base uses in-memory transport (no process spawn)
 
-model = "claude-sonnet-4-5"
+model = "claude-haiku-4-5"
 
 [provider]
 providerName = "anthropic"
diff --git a/e2e/experts/cli-commands.toml b/e2e/experts/cli-commands.toml
index 30e3fe0e..085986fa 100644
--- a/e2e/experts/cli-commands.toml
+++ b/e2e/experts/cli-commands.toml
@@ -1,4 +1,4 @@
-model = "claude-sonnet-4-5"
+model = "claude-haiku-4-5"
 
 [provider]
 providerName = "anthropic"
diff --git a/e2e/experts/continue-resume.toml b/e2e/experts/continue-resume.toml
index 71008b46..18e8fc46 100644
--- a/e2e/experts/continue-resume.toml
+++ b/e2e/experts/continue-resume.toml
@@ -1,4 +1,4 @@
-model = "claude-sonnet-4-5"
+model = "claude-haiku-4-5"
 
 [provider]
 providerName = "anthropic"
diff --git a/e2e/experts/delegate-chain.toml b/e2e/experts/delegate-chain.toml
index 55055572..5eedff64 100644
--- a/e2e/experts/delegate-chain.toml
+++ b/e2e/experts/delegate-chain.toml
@@ -1,4 +1,4 @@
-model = "claude-sonnet-4-5"
+model = "claude-haiku-4-5"
 
 [provider]
 providerName = "anthropic"
diff --git a/e2e/experts/error-handling.toml b/e2e/experts/error-handling.toml
index 222313f0..e52f496e 100644
--- a/e2e/experts/error-handling.toml
+++ b/e2e/experts/error-handling.toml
@@ -1,4 +1,4 @@
-model = "claude-sonnet-4-5"
+model = "claude-haiku-4-5"
 
 [provider]
 providerName = "anthropic"
diff --git a/e2e/experts/errors.toml b/e2e/experts/errors.toml
index 73043a0e..771a20b5 100644
--- a/e2e/experts/errors.toml
+++ b/e2e/experts/errors.toml
@@ -1,4 +1,4 @@
-model = "claude-sonnet-4-5"
+model = "claude-haiku-4-5"
 
 [provider]
 providerName = "anthropic"
diff --git a/e2e/experts/global-runtime.toml b/e2e/experts/global-runtime.toml
index 2b6cfbaa..a367b869 100644
--- a/e2e/experts/global-runtime.toml
+++ b/e2e/experts/global-runtime.toml
@@ -1,4 +1,4 @@
-model = "claude-sonnet-4-5"
+model = "claude-haiku-4-5"
 
 [provider]
 providerName = "anthropic"
diff --git a/e2e/experts/lazy-init.toml b/e2e/experts/lazy-init.toml
index f23ce174..0bb317a6 100644
--- a/e2e/experts/lazy-init.toml
+++ b/e2e/experts/lazy-init.toml
@@ -1,4 +1,4 @@
-model = "claude-sonnet-4-5"
+model = "claude-haiku-4-5"
 
 [provider]
 providerName = "anthropic"
diff --git a/e2e/experts/lockfile.toml b/e2e/experts/lockfile.toml
index 0cd4e032..28bd6f85 100644
--- a/e2e/experts/lockfile.toml
+++ b/e2e/experts/lockfile.toml
@@ -1,7 +1,7 @@
 # E2E test configuration for lockfile functionality
 # Tests perstack install and lockfile-based execution
 
-model = "claude-sonnet-4-5"
+model = "claude-haiku-4-5"
 
 [provider]
 providerName = "anthropic"
diff --git a/e2e/experts/mixed-tools.toml b/e2e/experts/mixed-tools.toml
index cd7244fb..d8207b07 100644
--- a/e2e/experts/mixed-tools.toml
+++ b/e2e/experts/mixed-tools.toml
@@ -1,4 +1,4 @@
-model = "claude-sonnet-4-5"
+model = "claude-haiku-4-5"
 
 [provider]
 providerName = "anthropic"
diff --git a/e2e/experts/multi-modal.toml b/e2e/experts/multi-modal.toml
index d135cb26..8595784d 100644
--- a/e2e/experts/multi-modal.toml
+++ b/e2e/experts/multi-modal.toml
@@ -1,4 +1,4 @@
-model = "claude-sonnet-4-5"
+model = "claude-haiku-4-5"
 
 [provider]
 providerName = "anthropic"
diff --git a/e2e/experts/parallel-delegate.toml b/e2e/experts/parallel-delegate.toml
index 028d47cf..bb08ace9 100644
--- a/e2e/experts/parallel-delegate.toml
+++ b/e2e/experts/parallel-delegate.toml
@@ -1,4 +1,4 @@
-model = "claude-sonnet-4-5"
+model = "claude-haiku-4-5"
 
 [provider]
 providerName = "anthropic"
diff --git a/e2e/experts/parallel-mcp.toml b/e2e/experts/parallel-mcp.toml
index 82a4735a..81908cdf 100644
--- a/e2e/experts/parallel-mcp.toml
+++ b/e2e/experts/parallel-mcp.toml
@@ -1,4 +1,4 @@
-model = "claude-sonnet-4-5"
+model = "claude-haiku-4-5"
 
 [provider]
 providerName = "anthropic"
diff --git a/e2e/experts/runtime-version-future.toml b/e2e/experts/runtime-version-future.toml
index d9afec29..b5e79f0d 100644
--- a/e2e/experts/runtime-version-future.toml
+++ b/e2e/experts/runtime-version-future.toml
@@ -1,4 +1,4 @@
-model = "claude-sonnet-4-5"
+model = "claude-haiku-4-5"
 
 [provider]
 providerName = "anthropic"
diff --git a/e2e/experts/runtime-version.toml b/e2e/experts/runtime-version.toml
index ab82ec5a..55796b4e 100644
--- a/e2e/experts/runtime-version.toml
+++ b/e2e/experts/runtime-version.toml
@@ -1,4 +1,4 @@
-model = "claude-sonnet-4-5"
+model = "claude-haiku-4-5"
 
 [provider]
 providerName = "anthropic"
diff --git a/e2e/experts/skills.toml b/e2e/experts/skills.toml
index eeac3271..0d93c255 100644
--- a/e2e/experts/skills.toml
+++ b/e2e/experts/skills.toml
@@ -1,4 +1,4 @@
-model = "claude-sonnet-4-5"
+model = "claude-haiku-4-5"
 
 [provider]
 providerName = "anthropic"
diff --git a/e2e/experts/special-tools.toml b/e2e/experts/special-tools.toml
index 67a7d514..5dd91402 100644
--- a/e2e/experts/special-tools.toml
+++ b/e2e/experts/special-tools.toml
@@ -1,4 +1,4 @@
-model = "claude-sonnet-4-5"
+model = "claude-haiku-4-5"
 
 [provider]
 providerName = "anthropic"
diff --git a/e2e/experts/versioned-base.toml b/e2e/experts/versioned-base.toml
index 2ac8890b..9ff3ce3a 100644
--- a/e2e/experts/versioned-base.toml
+++ b/e2e/experts/versioned-base.toml
@@ -1,7 +1,7 @@
 # E2E test configuration for versioned base skill with StdioTransport
 # Tests that pinning a version falls back to npx (StdioTransport)
 
-model = "claude-sonnet-4-5"
+model = "claude-haiku-4-5"
 
 [provider]
 providerName = "anthropic"
diff --git a/e2e/perstack-cli/options.test.ts b/e2e/perstack-cli/options.test.ts
index f22cbe74..33c72a62 100644
--- a/e2e/perstack-cli/options.test.ts
+++ b/e2e/perstack-cli/options.test.ts
@@ -48,7 +48,7 @@ describe.concurrent("CLI Options", () => {
           "--config",
           GLOBAL_RUNTIME_CONFIG,
           "--model",
-          "claude-sonnet-4-5",
+          "claude-haiku-4-5",
           "e2e-global-runtime",
           "Say hello",
         ],
diff --git a/e2e/perstack-cli/providers.test.ts b/e2e/perstack-cli/providers.test.ts
index 680da3fc..dcf1e1fe 100644
--- a/e2e/perstack-cli/providers.test.ts
+++ b/e2e/perstack-cli/providers.test.ts
@@ -19,7 +19,7 @@ const CONFIG = "./e2e/experts/providers.toml"
 const LLM_TIMEOUT = 120000
 
 const providers = [
-  { provider: "openai", model: "gpt-4.1", hasKey: hasOpenAIKey },
+  { provider: "openai", model: "gpt-5-nano", hasKey: hasOpenAIKey },
   { provider: "anthropic", model: "claude-haiku-4-5", hasKey: hasAnthropicKey },
   { provider: "google", model: "gemini-2.5-flash", hasKey: hasGoogleKey },
 ]
diff --git a/e2e/perstack-cli/reasoning-budget.test.ts b/e2e/perstack-cli/reasoning-budget.test.ts
index a30c06f6..ebe2d7d6 100644
--- a/e2e/perstack-cli/reasoning-budget.test.ts
+++ b/e2e/perstack-cli/reasoning-budget.test.ts
@@ -97,8 +97,8 @@ async function runReasoningTest(
 
 describe("Reasoning Budget", () => {
   describe("Anthropic Extended Thinking", () => {
-    // Note: Claude claude-sonnet-4-5 supports extended thinking
-    const ANTHROPIC_MODEL = "claude-sonnet-4-5"
+    // Note: Claude claude-haiku-4-5 supports extended thinking
+    const ANTHROPIC_MODEL = "claude-haiku-4-5"
 
     it(
       "should produce reasoning tokens when budget is set",
@@ -152,8 +152,8 @@ describe("Reasoning Budget", () => {
   })
 
   describe("OpenAI Reasoning Effort", () => {
-    // Note: o3-mini supports reasoning effort
-    const OPENAI_MODEL = "o3-mini"
+    // Note: gpt-5-nano supports reasoning effort
+    const OPENAI_MODEL = "gpt-5-nano"
 
     it(
       "should produce reasoning tokens when budget is set",
diff --git a/e2e/perstack-cli/streaming.test.ts b/e2e/perstack-cli/streaming.test.ts
index 29a01ee0..77618c2a 100644
--- a/e2e/perstack-cli/streaming.test.ts
+++ b/e2e/perstack-cli/streaming.test.ts
@@ -32,7 +32,7 @@ function filterStreamingEvents(events: ParsedEvent[]): ParsedEvent[] {
 
 describe("Streaming Events", () => {
   describe("Event Sequence with Reasoning", () => {
-    const ANTHROPIC_MODEL = "claude-sonnet-4-5"
+    const ANTHROPIC_MODEL = "claude-haiku-4-5"
 
     it(
       "emits reasoning events in correct order (start → stream... → complete)",
@@ -180,7 +180,7 @@ describe("Streaming Events", () => {
 
   describe("Without Reasoning", () => {
     // Use a model/provider without reasoning or with reasoning disabled
-    const ANTHROPIC_MODEL = "claude-sonnet-4-20250514"
+    const ANTHROPIC_MODEL = "claude-haiku-4-5"
 
     it(
       "skips reasoning events when budget is none",
@@ -220,7 +220,7 @@ describe("Streaming Events", () => {
   })
 
   describe("Streaming Delta Content", () => {
-    const ANTHROPIC_MODEL = "claude-sonnet-4-5"
+    const ANTHROPIC_MODEL = "claude-haiku-4-5"
 
     it(
       "streamReasoning events contain non-empty deltas",
diff --git a/packages/core/src/known-models/index.ts b/packages/core/src/known-models/index.ts
index b20ba2c9..0f1c3488 100644
--- a/packages/core/src/known-models/index.ts
+++ b/packages/core/src/known-models/index.ts
@@ -3,6 +3,11 @@ export const knownModels = [
     provider: "anthropic",
     models: [
       // https://docs.claude.com/en/docs/about-claude/models/overview#model-comparison-table
+      {
+        name: "claude-opus-4-6",
+        contextWindow: 200_000,
+        maxOutputTokens: 128_000,
+      },
       {
         name: "claude-opus-4-5",
         contextWindow: 200_000,
@@ -48,6 +53,12 @@ export const knownModels = [
   {
     provider: "google",
     models: [
+      // https://ai.google.dev/gemini-api/docs/models#gemini-3-flash
+      {
+        name: "gemini-3-flash-preview",
+        contextWindow: 1_048_576,
+        maxOutputTokens: 65_536,
+      },
       // https://ai.google.dev/gemini-api/docs/models#gemini-3-pro
       {
         name: "gemini-3-pro-preview",
@@ -95,6 +106,24 @@ export const knownModels = [
         contextWindow: 400_000,
         maxOutputTokens: 128_000,
       },
+      // https://platform.openai.com/docs/models/gpt-5.2
+      {
+        name: "gpt-5.2",
+        contextWindow: 400_000,
+        maxOutputTokens: 128_000,
+      },
+      // https://platform.openai.com/docs/models/gpt-5.2-pro
+      {
+        name: "gpt-5.2-pro",
+        contextWindow: 400_000,
+        maxOutputTokens: 128_000,
+      },
+      // https://platform.openai.com/docs/models/gpt-5.1
+      {
+        name: "gpt-5.1",
+        contextWindow: 400_000,
+        maxOutputTokens: 128_000,
+      },
       // https://platform.openai.com/docs/models/gpt-5-chat-latest
       {
         name: "gpt-5-chat-latest",