From 6429781e8fc7ec5d72aedb7b2409f26f0c739e00 Mon Sep 17 00:00:00 2001
From: Tam Nhu Tran <kaitran.ntt@gmail.com>
Date: Sat, 21 Feb 2026 02:14:09 +0700
Subject: [PATCH] fix(cliproxy): normalize provider-aware Claude model IDs

---
 src/cliproxy/config/env-builder.ts            |  40 ++++---
 src/cliproxy/config/thinking-config.ts        |  10 +-
 src/cliproxy/executor/env-resolver.ts         |   6 +-
 src/cliproxy/index.ts                         |  10 ++
 src/cliproxy/model-catalog.ts                 |   8 +-
 src/cliproxy/model-id-normalizer.ts           | 104 ++++++++++++++++++
 src/cliproxy/tool-sanitization-proxy.ts       |  24 +++-
 .../cliproxy/composite-env-routing.test.ts    |  21 ++++
 .../unit/cliproxy/composite-thinking.test.ts  |  19 ++++
 .../cliproxy/env-builder-provider-url.test.ts |  25 ++++-
 .../cliproxy/model-catalog-compat.test.ts     |  17 +++
 .../unit/cliproxy/model-id-normalizer.test.ts |  85 ++++++++++++++
 ...ool-sanitization-proxy-integration.test.ts |  71 ++++++++++++
 13 files changed, 408 insertions(+), 32 deletions(-)
 create mode 100644 src/cliproxy/model-id-normalizer.ts
 create mode 100644 tests/unit/cliproxy/model-catalog-compat.test.ts
 create mode 100644 tests/unit/cliproxy/model-id-normalizer.test.ts

diff --git a/src/cliproxy/config/env-builder.ts b/src/cliproxy/config/env-builder.ts
index d4353572..277f4d41 100644
--- a/src/cliproxy/config/env-builder.ts
+++ b/src/cliproxy/config/env-builder.ts
@@ -19,6 +19,11 @@ import {
   CLIPROXY_DEFAULT_PORT,
 } from './port-manager';
 import { getProviderSettingsPath } from './path-resolver';
+import {
+  MODEL_ENV_VAR_KEYS,
+  normalizeModelEnvVarsForProvider,
+  normalizeModelIdForProvider,
+} from '../model-id-normalizer';
 
 /** Settings file structure for user overrides */
 interface ProviderSettings {
@@ -30,14 +35,6 @@ const DEPRECATED_MODEL_PREFIX = 'gemini-claude-';
 /** Replacement prefix matching actual upstream model names */
 const UPSTREAM_MODEL_PREFIX = 'claude-';
 
-/** Env vars that contain model names and may need migration */
-const MODEL_ENV_KEYS = [
-  'ANTHROPIC_MODEL',
-  'ANTHROPIC_DEFAULT_OPUS_MODEL',
-  'ANTHROPIC_DEFAULT_SONNET_MODEL',
-  'ANTHROPIC_DEFAULT_HAIKU_MODEL',
-];
-
 /**
  * Migrate deprecated gemini-claude-* model names to upstream claude-* names in a settings file.
  * CLIProxyAPI registry no longer recognizes the gemini-claude-* prefix convention.
@@ -49,7 +46,7 @@ function migrateDeprecatedModelNames(settingsPath: string, settings: ProviderSet
   if (!settings.env || typeof settings.env !== 'object') return false;
 
   let migrated = false;
-  for (const key of MODEL_ENV_KEYS) {
+  for (const key of MODEL_ENV_VAR_KEYS) {
     const value = settings.env[key];
     if (typeof value !== 'string') continue;
 
@@ -124,10 +121,12 @@ export function getClaudeEnvVars(
   } = baseEnvVars;
 
   // Merge core env vars with additional env vars from base config
-  return {
+  const mergedEnv = {
     ...coreEnvVars,
     ...additionalEnvVars, // Includes ANTHROPIC_MAX_TOKENS, etc.
   };
+
+  return normalizeModelEnvVarsForProvider(mergedEnv, provider);
 }
 
 /**
@@ -174,7 +173,7 @@ function ensureRequiredEnvVars(
     );
   }
 
-  return result;
+  return normalizeModelEnvVarsForProvider(result, provider);
 }
 
 /** Localhost hostnames used for local CLIProxy endpoints */
@@ -458,7 +457,7 @@ export function getRemoteEnvVars(
     ANTHROPIC_AUTH_TOKEN: remoteConfig.authToken || getEffectiveApiKey(),
   };
 
-  return env;
+  return normalizeModelEnvVarsForProvider(env, provider) as Record<string, string>;
 }
 
 /** Remote config for composite variant (passed from env-resolver) */
@@ -519,10 +518,19 @@ export function getCompositeEnvVars(
   const validPort = validatePort(port);
 
   // Defensive: handle missing tiers gracefully
-  const opusModel = tiers.opus?.model;
-  const sonnetModel = tiers.sonnet?.model;
-  const haikuModel = tiers.haiku?.model;
-  const defaultModel = tiers[defaultTier]?.model;
+  const opusModel = tiers.opus?.model
+    ? normalizeModelIdForProvider(tiers.opus.model, tiers.opus.provider)
+    : undefined;
+  const sonnetModel = tiers.sonnet?.model
+    ? normalizeModelIdForProvider(tiers.sonnet.model, tiers.sonnet.provider)
+    : undefined;
+  const haikuModel = tiers.haiku?.model
+    ? normalizeModelIdForProvider(tiers.haiku.model, tiers.haiku.provider)
+    : undefined;
+  const defaultTierModel = tiers[defaultTier];
+  const defaultModel = defaultTierModel?.model
+    ? normalizeModelIdForProvider(defaultTierModel.model, defaultTierModel.provider)
+    : undefined;
 
   // If default tier is missing, we cannot proceed meaningfully
   if (!defaultModel) {
diff --git a/src/cliproxy/config/thinking-config.ts b/src/cliproxy/config/thinking-config.ts
index 840b87e3..76e67752 100644
--- a/src/cliproxy/config/thinking-config.ts
+++ b/src/cliproxy/config/thinking-config.ts
@@ -8,6 +8,7 @@ import { ThinkingConfig, DEFAULT_THINKING_TIER_DEFAULTS } from '../../config/uni
 import { getThinkingConfig } from '../../config/unified-config-loader';
 import { supportsThinking } from '../model-catalog';
 import { isThinkingOffValue, validateThinking } from '../thinking-validator';
+import { normalizeModelIdForProvider } from '../model-id-normalizer';
 import { warn } from '../../utils/ui';
 
 /** Model tier types for thinking budget defaults */
@@ -19,22 +20,23 @@ export type ModelTier = 'opus' | 'sonnet' | 'haiku';
  */
 function normalizeModelForThinkingLookup(model: string, provider: CLIProxyProvider): string {
   const withoutExtendedContext = model.replace(/\[1m\]$/i, '').trim();
+  const providerNormalized = normalizeModelIdForProvider(withoutExtendedContext, provider);
 
-  if (provider !== 'codex') return withoutExtendedContext;
+  if (provider !== 'codex') return providerNormalized;
 
   // New codex suffix form: gpt-5.3-codex-high -> gpt-5.3-codex
-  const codexSuffixMatch = withoutExtendedContext.match(/^(.*)-(xhigh|high|medium)$/i);
+  const codexSuffixMatch = providerNormalized.match(/^(.*)-(xhigh|high|medium)$/i);
   if (codexSuffixMatch?.[1]) {
     return codexSuffixMatch[1].trim();
   }
 
   // Legacy codex suffix form: gpt-5.3-codex(high) -> gpt-5.3-codex
-  const codexLegacyMatch = withoutExtendedContext.match(/^(.*)\((xhigh|high|medium)\)$/i);
+  const codexLegacyMatch = providerNormalized.match(/^(.*)\((xhigh|high|medium)\)$/i);
   if (codexLegacyMatch?.[1]) {
     return codexLegacyMatch[1].trim();
   }
 
-  return withoutExtendedContext;
+  return providerNormalized;
 }
 
 /**
diff --git a/src/cliproxy/executor/env-resolver.ts b/src/cliproxy/executor/env-resolver.ts
index ea9dbcdb..ace7a18d 100644
--- a/src/cliproxy/executor/env-resolver.ts
+++ b/src/cliproxy/executor/env-resolver.ts
@@ -24,6 +24,7 @@ import { stripClaudeCodeEnv } from '../../utils/shell-executor';
 import { CodexReasoningProxy } from '../codex-reasoning-proxy';
 import { ToolSanitizationProxy } from '../tool-sanitization-proxy';
 import { HttpsTunnelProxy } from '../https-tunnel-proxy';
+import { normalizeModelIdForProvider } from '../model-id-normalizer';
 
 export interface RemoteProxyConfig {
   host: string;
@@ -271,10 +272,11 @@ export function applyFallback(
   } as const;
   const result = { ...env };
   const originalModel = result[tierEnvMap[failedTier]];
-  result[tierEnvMap[failedTier]] = fallback.model;
+  const normalizedFallbackModel = normalizeModelIdForProvider(fallback.model, fallback.provider);
+  result[tierEnvMap[failedTier]] = normalizedFallbackModel;
   // If failed tier is default tier, also update ANTHROPIC_MODEL
   if (result.ANTHROPIC_MODEL === originalModel) {
-    result.ANTHROPIC_MODEL = fallback.model;
+    result.ANTHROPIC_MODEL = normalizedFallbackModel;
   }
   return result;
 }
diff --git a/src/cliproxy/index.ts b/src/cliproxy/index.ts
index 0975e3cb..a250bb2d 100644
--- a/src/cliproxy/index.ts
+++ b/src/cliproxy/index.ts
@@ -84,6 +84,16 @@ export {
 // Model catalog and configuration
 export type { ModelEntry, ProviderCatalog } from './model-catalog';
 export { MODEL_CATALOG, supportsModelConfig, getProviderCatalog, findModel } from './model-catalog';
+export {
+  MODEL_ENV_VAR_KEYS,
+  extractProviderFromPathname,
+  isAntigravityProvider,
+  normalizeClaudeDottedMajorMinor,
+  normalizeClaudeDottedThinkingMajorMinor,
+  normalizeModelIdForProvider,
+  normalizeModelIdForRouting,
+  normalizeModelEnvVarsForProvider,
+} from './model-id-normalizer';
 export {
   hasUserSettings,
   getCurrentModel,
diff --git a/src/cliproxy/model-catalog.ts b/src/cliproxy/model-catalog.ts
index e03d6b6a..13b6c45c 100644
--- a/src/cliproxy/model-catalog.ts
+++ b/src/cliproxy/model-catalog.ts
@@ -6,6 +6,7 @@
  */
 
 import { CLIProxyProvider } from './types';
+import { normalizeModelIdForProvider } from './model-id-normalizer';
 
 /**
  * Thinking support configuration for a model.
@@ -322,7 +323,12 @@ export function findModel(provider: CLIProxyProvider, modelId: string): ModelEnt
   const catalog = MODEL_CATALOG[provider];
   if (!catalog || !modelId) return undefined;
   const normalizedId = modelId.trim().toLowerCase();
-  return catalog.models.find((m) => m.id.toLowerCase() === normalizedId);
+  const providerNormalizedId = normalizeModelIdForProvider(normalizedId, provider)
+    .trim()
+    .toLowerCase();
+  const lookupCandidates = new Set([normalizedId, providerNormalizedId]);
+
+  return catalog.models.find((m) => lookupCandidates.has(m.id.toLowerCase()));
 }
 
 /**
diff --git a/src/cliproxy/model-id-normalizer.ts b/src/cliproxy/model-id-normalizer.ts
new file mode 100644
index 00000000..7d8ee86b
--- /dev/null
+++ b/src/cliproxy/model-id-normalizer.ts
@@ -0,0 +1,104 @@
+/**
+ * Model ID normalization helpers.
+ *
+ * Handles provider-aware compatibility between dotted and hyphenated Claude
+ * model version formats (e.g., 4.6 vs 4-6).
+ */
+
+import { CLIProxyProvider } from './types';
+
+/** Env vars that carry model identifiers. */
+export const MODEL_ENV_VAR_KEYS = [
+  'ANTHROPIC_MODEL',
+  'ANTHROPIC_DEFAULT_OPUS_MODEL',
+  'ANTHROPIC_DEFAULT_SONNET_MODEL',
+  'ANTHROPIC_DEFAULT_HAIKU_MODEL',
+] as const;
+
+type ProviderLike = CLIProxyProvider | string | null | undefined;
+
+const CLAUDE_DOTTED_VERSION_REGEX = /claude-(sonnet|opus|haiku)-(\d+)\.(\d+)(?=(?:$|-|\[|\(|\/))/gi;
+const CLAUDE_DOTTED_THINKING_REGEX =
+  /claude-(sonnet|opus|haiku)-(\d+)\.(\d+)-thinking(?=(?:$|-|\[|\(|\/))/gi;
+
+/** Extract provider segment from /api/provider/{provider} paths. */
+export function extractProviderFromPathname(pathname: string): string | null {
+  const match = pathname.match(/\/api\/provider\/([^/]+)/i);
+  if (!match?.[1]) return null;
+  return match[1].toLowerCase();
+}
+
+/** Whether the provider uses Antigravity model routing conventions. */
+export function isAntigravityProvider(provider: ProviderLike): boolean {
+  if (typeof provider !== 'string') return false;
+  const normalized = provider.trim().toLowerCase();
+  return normalized === 'agy' || normalized === 'antigravity';
+}
+
+/** Normalize Claude dotted major.minor IDs to hyphenated format. */
+export function normalizeClaudeDottedMajorMinor(model: string): string {
+  return model.replace(
+    CLAUDE_DOTTED_VERSION_REGEX,
+    (_match: string, family: string, major: string, minor: string) =>
+      `claude-${family.toLowerCase()}-${major}-${minor}`
+  );
+}
+
+/**
+ * Normalize only dotted Claude thinking IDs to hyphenated format.
+ * Keeps non-thinking dotted IDs unchanged.
+ */
+export function normalizeClaudeDottedThinkingMajorMinor(model: string): string {
+  return model.replace(
+    CLAUDE_DOTTED_THINKING_REGEX,
+    (_match: string, family: string, major: string, minor: string) =>
+      `claude-${family.toLowerCase()}-${major}-${minor}-thinking`
+  );
+}
+
+/**
+ * Normalize model ID for a specific provider.
+ * Antigravity requires hyphenated Claude major.minor model IDs.
+ */
+export function normalizeModelIdForProvider(model: string, provider: ProviderLike): string {
+  if (!isAntigravityProvider(provider)) return model;
+  return normalizeClaudeDottedMajorMinor(model);
+}
+
+/**
+ * Normalize model ID for request routing.
+ * - Antigravity routes: normalize all dotted Claude major.minor forms.
+ * - Root/composite routes: normalize only thinking forms to avoid mutating
+ *   valid non-thinking dotted IDs used by other providers.
+ */
+export function normalizeModelIdForRouting(model: string, provider: ProviderLike): string {
+  if (isAntigravityProvider(provider)) {
+    return normalizeClaudeDottedMajorMinor(model);
+  }
+  return normalizeClaudeDottedThinkingMajorMinor(model);
+}
+
+/**
+ * Normalize model-related env vars for a provider.
+ * Returns original object when no changes are required.
+ */
+export function normalizeModelEnvVarsForProvider(
+  envVars: NodeJS.ProcessEnv,
+  provider: ProviderLike,
+  keys: readonly string[] = MODEL_ENV_VAR_KEYS
+): NodeJS.ProcessEnv {
+  let nextEnv: NodeJS.ProcessEnv | null = null;
+
+  for (const key of keys) {
+    const value = envVars[key];
+    if (typeof value !== 'string' || value.trim().length === 0) continue;
+
+    const normalizedValue = normalizeModelIdForProvider(value, provider);
+    if (normalizedValue === value) continue;
+
+    if (!nextEnv) nextEnv = { ...envVars };
+    nextEnv[key] = normalizedValue;
+  }
+
+  return nextEnv ?? envVars;
+}
diff --git a/src/cliproxy/tool-sanitization-proxy.ts b/src/cliproxy/tool-sanitization-proxy.ts
index 36c7c40f..3dc0b379 100644
--- a/src/cliproxy/tool-sanitization-proxy.ts
+++ b/src/cliproxy/tool-sanitization-proxy.ts
@@ -18,6 +18,7 @@ import * as os from 'os';
 import { URL } from 'url';
 import { ToolNameMapper, type Tool, type ContentBlock } from './tool-name-mapper';
 import { sanitizeToolSchemas } from './schema-sanitizer';
+import { extractProviderFromPathname, normalizeModelIdForRouting } from './model-id-normalizer';
 import { getCcsDir } from '../utils/config-manager';
 
 export interface ToolSanitizationProxyConfig {
@@ -206,12 +207,25 @@ export class ToolSanitizationProxy {
       // Create mapper for this request
       const mapper = new ToolNameMapper();
 
-      // Sanitize tools if present
+      // Normalize dotted Claude model IDs for provider-compatible routing.
       let modifiedBody = parsed;
-      if (isRecord(parsed) && Array.isArray(parsed.tools)) {
+      if (isRecord(modifiedBody) && typeof modifiedBody.model === 'string') {
+        const providerFromPath = extractProviderFromPathname(fullUpstreamUrl.pathname);
+        const normalizedModel = normalizeModelIdForRouting(modifiedBody.model, providerFromPath);
+        if (normalizedModel !== modifiedBody.model) {
+          this.writeLog(
+            'warn',
+            `[tool-sanitization-proxy] Model normalized for provider routing (${providerFromPath ?? 'root'}): "${modifiedBody.model}" → "${normalizedModel}"`
+          );
+          modifiedBody = { ...modifiedBody, model: normalizedModel };
+        }
+      }
+
+      // Sanitize tools if present
+      if (isRecord(modifiedBody) && Array.isArray(modifiedBody.tools)) {
         // Step 1: Sanitize input_schema properties (remove non-standard JSON Schema properties)
         const schemaResult = sanitizeToolSchemas(
-          parsed.tools as Array<{ name: string; input_schema?: Record<string, unknown> }>
+          modifiedBody.tools as Array<{ name: string; input_schema?: Record<string, unknown> }>
         );
 
         if (schemaResult.totalRemoved > 0) {
@@ -228,7 +242,7 @@ export class ToolSanitizationProxy {
 
         // Step 2: Sanitize tool names (truncate to 64 chars for Gemini)
         const sanitizedTools = mapper.registerTools(schemaResult.tools as Tool[]);
-        modifiedBody = { ...parsed, tools: sanitizedTools };
+        modifiedBody = { ...modifiedBody, tools: sanitizedTools };
 
         // Log sanitization warnings
         if (mapper.hasChanges()) {
@@ -252,7 +266,7 @@ export class ToolSanitizationProxy {
       }
 
       // Check if streaming is requested
-      const isStreaming = isRecord(parsed) && parsed.stream === true;
+      const isStreaming = isRecord(modifiedBody) && modifiedBody.stream === true;
 
       if (isStreaming) {
         await this.forwardJsonStreaming(req, res, fullUpstreamUrl, modifiedBody, mapper);
diff --git a/tests/unit/cliproxy/composite-env-routing.test.ts b/tests/unit/cliproxy/composite-env-routing.test.ts
index 18978f21..281aae1b 100644
--- a/tests/unit/cliproxy/composite-env-routing.test.ts
+++ b/tests/unit/cliproxy/composite-env-routing.test.ts
@@ -71,4 +71,25 @@ describe('buildClaudeEnvironment - composite remote routing', () => {
     // Gemini thinking overrides may be normalized to numeric budgets, and [1m] may be auto-appended.
     expect(env.ANTHROPIC_MODEL).toMatch(/\([^)]+\)(\[1m\])?$/);
   });
+
+  it('normalizes dotted Claude model IDs for antigravity tiers in composite mode', () => {
+    const env = buildClaudeEnvironment({
+      provider: 'agy',
+      useRemoteProxy: false,
+      localPort: 8318,
+      verbose: false,
+      isComposite: true,
+      compositeTiers: {
+        opus: { provider: 'agy', model: 'claude-opus-4.6-thinking' },
+        sonnet: { provider: 'gemini', model: 'gemini-2.5-pro' },
+        haiku: { provider: 'codex', model: 'gpt-5.1-codex-mini' },
+      },
+      compositeDefaultTier: 'opus',
+    });
+
+    expect(env.ANTHROPIC_MODEL).toMatch(/^claude-opus-4-6-thinking(\([^)]+\))?$/);
+    expect(env.ANTHROPIC_DEFAULT_OPUS_MODEL).toMatch(/^claude-opus-4-6-thinking(\([^)]+\))?$/);
+    expect(env.ANTHROPIC_DEFAULT_SONNET_MODEL).toMatch(/^gemini-2.5-pro(\([^)]+\))?$/);
+    expect(env.ANTHROPIC_DEFAULT_HAIKU_MODEL).toBe('gpt-5.1-codex-mini');
+  });
 });
diff --git a/tests/unit/cliproxy/composite-thinking.test.ts b/tests/unit/cliproxy/composite-thinking.test.ts
index 4f66dad4..fe1ad59c 100644
--- a/tests/unit/cliproxy/composite-thinking.test.ts
+++ b/tests/unit/cliproxy/composite-thinking.test.ts
@@ -378,6 +378,25 @@ describe('applyThinkingConfig - composite variant integration', () => {
     expect(result.ANTHROPIC_DEFAULT_SONNET_MODEL).toBe('claude-sonnet-4-5-thinking(high)');
   });
 
+  it('handles dotted agy Claude IDs for thinking capability lookup', () => {
+    const envVars: NodeJS.ProcessEnv = {
+      ANTHROPIC_MODEL: 'claude-opus-4.5-thinking',
+      ANTHROPIC_DEFAULT_OPUS_MODEL: 'claude-opus-4.5-thinking',
+      ANTHROPIC_DEFAULT_SONNET_MODEL: 'claude-sonnet-4.5-thinking',
+      ANTHROPIC_DEFAULT_HAIKU_MODEL: 'claude-haiku-4.5',
+    };
+
+    const result = applyThinkingConfig(envVars, 'agy' as CLIProxyProvider, 'high');
+
+    // Capability lookup should succeed for dotted agy IDs after normalization.
+    // Main model value is validated for budget models; tier values keep raw override.
+    expect(result.ANTHROPIC_MODEL).toBe('claude-opus-4.5-thinking(24576)');
+    expect(result.ANTHROPIC_DEFAULT_OPUS_MODEL).toBe('claude-opus-4.5-thinking(high)');
+    expect(result.ANTHROPIC_DEFAULT_SONNET_MODEL).toBe('claude-sonnet-4.5-thinking(high)');
+    // Haiku does not support thinking in agy catalog.
+    expect(result.ANTHROPIC_DEFAULT_HAIKU_MODEL).toBe('claude-haiku-4.5');
+  });
+
   it('should handle numeric budgets in per-tier thinking', () => {
     const envVars: NodeJS.ProcessEnv = {
       ANTHROPIC_MODEL: 'claude-sonnet-4-5-thinking',
diff --git a/tests/unit/cliproxy/env-builder-provider-url.test.ts b/tests/unit/cliproxy/env-builder-provider-url.test.ts
index 0705638c..bae0639d 100644
--- a/tests/unit/cliproxy/env-builder-provider-url.test.ts
+++ b/tests/unit/cliproxy/env-builder-provider-url.test.ts
@@ -13,7 +13,7 @@ interface EnvSettings {
   ANTHROPIC_DEFAULT_HAIKU_MODEL: string;
 }
 
-function writeCodexSettings(settingsPath: string, env: EnvSettings): void {
+function writeSettings(settingsPath: string, env: EnvSettings): void {
   fs.writeFileSync(settingsPath, JSON.stringify({ env }, null, 2));
 }
 
@@ -31,7 +31,7 @@ describe('getEffectiveEnvVars local provider URL normalization', () => {
   });
 
   it('rewrites local root URL to provider endpoint', () => {
-    writeCodexSettings(settingsPath, {
+    writeSettings(settingsPath, {
       ANTHROPIC_BASE_URL: 'http://127.0.0.1:8317',
       ANTHROPIC_AUTH_TOKEN: 'ccs-internal-managed',
       ANTHROPIC_MODEL: 'gpt-5.3-codex-xhigh',
@@ -45,7 +45,7 @@ describe('getEffectiveEnvVars local provider URL normalization', () => {
   });
 
   it('rewrites wrong local provider path to the requested provider', () => {
-    writeCodexSettings(settingsPath, {
+    writeSettings(settingsPath, {
       ANTHROPIC_BASE_URL: 'http://localhost:8317/api/provider/my-codex-variant?debug=1',
       ANTHROPIC_AUTH_TOKEN: 'ccs-internal-managed',
       ANTHROPIC_MODEL: 'gpt-5.3-codex-xhigh',
@@ -59,7 +59,7 @@ describe('getEffectiveEnvVars local provider URL normalization', () => {
   });
 
   it('does not rewrite localhost URLs targeting non-cliproxy ports', () => {
-    writeCodexSettings(settingsPath, {
+    writeSettings(settingsPath, {
       ANTHROPIC_BASE_URL: 'http://127.0.0.1:11434',
       ANTHROPIC_AUTH_TOKEN: 'ccs-internal-managed',
       ANTHROPIC_MODEL: 'gpt-5.3-codex-xhigh',
@@ -71,4 +71,21 @@ describe('getEffectiveEnvVars local provider URL normalization', () => {
     const env = getEffectiveEnvVars('codex', 8317, settingsPath);
     expect(env.ANTHROPIC_BASE_URL).toBe('http://127.0.0.1:11434');
   });
+
+  it('normalizes dotted Claude major.minor IDs for agy provider settings', () => {
+    writeSettings(settingsPath, {
+      ANTHROPIC_BASE_URL: 'http://127.0.0.1:8317/api/provider/agy',
+      ANTHROPIC_AUTH_TOKEN: 'ccs-internal-managed',
+      ANTHROPIC_MODEL: 'claude-sonnet-4.6-thinking',
+      ANTHROPIC_DEFAULT_OPUS_MODEL: 'claude-opus-4.6-thinking',
+      ANTHROPIC_DEFAULT_SONNET_MODEL: 'claude-sonnet-4.6-thinking',
+      ANTHROPIC_DEFAULT_HAIKU_MODEL: 'claude-haiku-4.5',
+    });
+
+    const env = getEffectiveEnvVars('agy', 8317, settingsPath);
+    expect(env.ANTHROPIC_MODEL).toBe('claude-sonnet-4-6-thinking');
+    expect(env.ANTHROPIC_DEFAULT_OPUS_MODEL).toBe('claude-opus-4-6-thinking');
+    expect(env.ANTHROPIC_DEFAULT_SONNET_MODEL).toBe('claude-sonnet-4-6-thinking');
+    expect(env.ANTHROPIC_DEFAULT_HAIKU_MODEL).toBe('claude-haiku-4-5');
+  });
 });
diff --git a/tests/unit/cliproxy/model-catalog-compat.test.ts b/tests/unit/cliproxy/model-catalog-compat.test.ts
new file mode 100644
index 00000000..90fad46f
--- /dev/null
+++ b/tests/unit/cliproxy/model-catalog-compat.test.ts
@@ -0,0 +1,17 @@
+import { describe, it, expect } from 'bun:test';
+import { findModel, supportsThinking } from '../../../src/cliproxy/model-catalog';
+
+describe('model-catalog compatibility lookups', () => {
+  it('finds agy Claude models using dotted major.minor IDs', () => {
+    const dottedThinking = findModel('agy', 'claude-sonnet-4.5-thinking');
+    const dottedNonThinking = findModel('agy', 'claude-sonnet-4.5');
+
+    expect(dottedThinking?.id).toBe('claude-sonnet-4-5-thinking');
+    expect(dottedNonThinking?.id).toBe('claude-sonnet-4-5');
+  });
+
+  it('supports thinking checks for dotted agy model IDs', () => {
+    expect(supportsThinking('agy', 'claude-opus-4.6-thinking')).toBe(true);
+    expect(supportsThinking('agy', 'claude-sonnet-4.5')).toBe(false);
+  });
+});
diff --git a/tests/unit/cliproxy/model-id-normalizer.test.ts b/tests/unit/cliproxy/model-id-normalizer.test.ts
new file mode 100644
index 00000000..d13bca6b
--- /dev/null
+++ b/tests/unit/cliproxy/model-id-normalizer.test.ts
@@ -0,0 +1,85 @@
+import { describe, it, expect } from 'bun:test';
+import {
+  extractProviderFromPathname,
+  isAntigravityProvider,
+  normalizeClaudeDottedMajorMinor,
+  normalizeClaudeDottedThinkingMajorMinor,
+  normalizeModelIdForProvider,
+  normalizeModelIdForRouting,
+  normalizeModelEnvVarsForProvider,
+} from '../../../src/cliproxy/model-id-normalizer';
+
+describe('model-id-normalizer', () => {
+  describe('provider parsing', () => {
+    it('extracts provider from provider route path', () => {
+      expect(extractProviderFromPathname('/api/provider/agy/v1/messages')).toBe('agy');
+      expect(extractProviderFromPathname('/api/provider/antigravity')).toBe('antigravity');
+      expect(extractProviderFromPathname('/v1/messages')).toBeNull();
+    });
+
+    it('detects antigravity provider aliases', () => {
+      expect(isAntigravityProvider('agy')).toBe(true);
+      expect(isAntigravityProvider('antigravity')).toBe(true);
+      expect(isAntigravityProvider('gemini')).toBe(false);
+      expect(isAntigravityProvider(undefined)).toBe(false);
+    });
+  });
+
+  describe('model normalization', () => {
+    it('normalizes dotted Claude major.minor to hyphen format', () => {
+      expect(normalizeClaudeDottedMajorMinor('claude-sonnet-4.6-thinking')).toBe(
+        'claude-sonnet-4-6-thinking'
+      );
+      expect(normalizeClaudeDottedMajorMinor('claude-opus-4.6')).toBe('claude-opus-4-6');
+    });
+
+    it('normalizes only dotted thinking variants for root/composite routing', () => {
+      expect(normalizeClaudeDottedThinkingMajorMinor('claude-sonnet-4.6-thinking')).toBe(
+        'claude-sonnet-4-6-thinking'
+      );
+      expect(normalizeClaudeDottedThinkingMajorMinor('claude-sonnet-4.6')).toBe(
+        'claude-sonnet-4.6'
+      );
+    });
+
+    it('applies provider-aware routing normalization', () => {
+      expect(normalizeModelIdForRouting('claude-sonnet-4.6-thinking', null)).toBe(
+        'claude-sonnet-4-6-thinking'
+      );
+      expect(normalizeModelIdForRouting('claude-sonnet-4.6', null)).toBe('claude-sonnet-4.6');
+      expect(normalizeModelIdForRouting('claude-sonnet-4.6', 'agy')).toBe('claude-sonnet-4-6');
+    });
+
+    it('applies provider-only normalization for antigravity', () => {
+      expect(normalizeModelIdForProvider('claude-opus-4.6-thinking', 'agy')).toBe(
+        'claude-opus-4-6-thinking'
+      );
+      expect(normalizeModelIdForProvider('claude-opus-4.6-thinking', 'gemini')).toBe(
+        'claude-opus-4.6-thinking'
+      );
+    });
+  });
+
+  describe('env normalization', () => {
+    it('normalizes model env vars for antigravity only', () => {
+      const input: NodeJS.ProcessEnv = {
+        ANTHROPIC_MODEL: 'claude-sonnet-4.6-thinking',
+        ANTHROPIC_DEFAULT_OPUS_MODEL: 'claude-opus-4.6-thinking',
+        ANTHROPIC_DEFAULT_SONNET_MODEL: 'claude-sonnet-4.6',
+        ANTHROPIC_DEFAULT_HAIKU_MODEL: 'claude-haiku-4.5',
+        UNRELATED: 'keep-me',
+      };
+
+      const normalized = normalizeModelEnvVarsForProvider(input, 'agy');
+      expect(normalized.ANTHROPIC_MODEL).toBe('claude-sonnet-4-6-thinking');
+      expect(normalized.ANTHROPIC_DEFAULT_OPUS_MODEL).toBe('claude-opus-4-6-thinking');
+      expect(normalized.ANTHROPIC_DEFAULT_SONNET_MODEL).toBe('claude-sonnet-4-6');
+      expect(normalized.ANTHROPIC_DEFAULT_HAIKU_MODEL).toBe('claude-haiku-4-5');
+      expect(normalized.UNRELATED).toBe('keep-me');
+
+      const unchanged = normalizeModelEnvVarsForProvider(input, 'gemini');
+      expect(unchanged.ANTHROPIC_MODEL).toBe('claude-sonnet-4.6-thinking');
+      expect(unchanged.UNRELATED).toBe('keep-me');
+    });
+  });
+});
diff --git a/tests/unit/cliproxy/tool-sanitization-proxy-integration.test.ts b/tests/unit/cliproxy/tool-sanitization-proxy-integration.test.ts
index 03a9bc5f..dd7dd2ac 100644
--- a/tests/unit/cliproxy/tool-sanitization-proxy-integration.test.ts
+++ b/tests/unit/cliproxy/tool-sanitization-proxy-integration.test.ts
@@ -184,6 +184,77 @@ describe('ToolSanitizationProxy Integration', () => {
       }
     });
 
+    it('normalizes dotted Claude thinking model IDs for root/composite routes', async () => {
+      const proxy = new ToolSanitizationProxy({
+        upstreamBaseUrl: `http://127.0.0.1:${mockUpstreamPort}`,
+      });
+      const port = await proxy.start();
+
+      try {
+        await fetch(`http://127.0.0.1:${port}/v1/messages`, {
+          method: 'POST',
+          headers: { 'Content-Type': 'application/json' },
+          body: JSON.stringify({
+            model: 'claude-sonnet-4.6-thinking',
+            messages: [{ role: 'user', content: 'test' }],
+          }),
+        });
+
+        expect(lastRequest).not.toBeNull();
+        expect((lastRequest!.body as Record<string, unknown>).model).toBe(
+          'claude-sonnet-4-6-thinking'
+        );
+      } finally {
+        proxy.stop();
+      }
+    });
+
+    it('keeps dotted non-thinking model IDs unchanged', async () => {
+      const proxy = new ToolSanitizationProxy({
+        upstreamBaseUrl: `http://127.0.0.1:${mockUpstreamPort}`,
+      });
+      const port = await proxy.start();
+
+      try {
+        await fetch(`http://127.0.0.1:${port}/v1/messages`, {
+          method: 'POST',
+          headers: { 'Content-Type': 'application/json' },
+          body: JSON.stringify({
+            model: 'claude-sonnet-4.5',
+            messages: [{ role: 'user', content: 'test' }],
+          }),
+        });
+
+        expect(lastRequest).not.toBeNull();
+        expect((lastRequest!.body as Record<string, unknown>).model).toBe('claude-sonnet-4.5');
+      } finally {
+        proxy.stop();
+      }
+    });
+
+    it('normalizes dotted Claude major.minor IDs on antigravity provider route', async () => {
+      const proxy = new ToolSanitizationProxy({
+        upstreamBaseUrl: `http://127.0.0.1:${mockUpstreamPort}`,
+      });
+      const port = await proxy.start();
+
+      try {
+        await fetch(`http://127.0.0.1:${port}/api/provider/agy/v1/messages`, {
+          method: 'POST',
+          headers: { 'Content-Type': 'application/json' },
+          body: JSON.stringify({
+            model: 'claude-opus-4.6',
+            messages: [{ role: 'user', content: 'test' }],
+          }),
+        });
+
+        expect(lastRequest).not.toBeNull();
+        expect((lastRequest!.body as Record<string, unknown>).model).toBe('claude-opus-4-6');
+      } finally {
+        proxy.stop();
+      }
+    });
+
     it('preserves other tool properties during sanitization', async () => {
       const proxy = new ToolSanitizationProxy({
         upstreamBaseUrl: `http://127.0.0.1:${mockUpstreamPort}`,