fix(server): Claude effort-cap model keys match like Claude Code

Claude Code names the model a modelSettings key caps more narrowly than the
catalog's aliases: only a family alias (opus, sonnet, haiku, fable, optionally
[1m]) resolves as an alias, and any other key names the most specific model id
it contains. Resolving keys through the catalog capped labels for dotted keys
such as claude-opus-5.5 that the CLI ignores, and missed dated or Bedrock ids
such as claude-opus-5-5-20260101 that it applies.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Author: juliusmarminge

apps/server/src/provider/ClaudeModelCatalog.test.ts

@@ -382,7 +382,7 @@ describe("Claude model catalog", () => {
       slug: "claude-opus-5-5",
       name: "Opus 5.5",
       isCustom: false,
-      aliases: ["opus"],
+      aliases: ["opus", "opus-5.5", "claude-opus-5.5"],
       capabilities: {
         optionDescriptors: [
           {
@@ -400,7 +400,19 @@ describe("Claude model catalog", () => {
       },
     };
     const catalog: ClaudeModelCatalog = {
-      models: [{ model: opus, runtime: {}, compatibility: {} }],
+      models: [
+        { model: opus, runtime: {}, compatibility: {} },
+        {
+          model: {
+            slug: "claude-opus-5",
+            name: "Opus 5",
+            isCustom: false,
+            capabilities: { optionDescriptors: [] },
+          },
+          runtime: {},
+          compatibility: {},
+        },
+      ],
     };
     const maxLabel = (sources: Parameters<typeof capClaudeCatalogEffort>[2]) => {
       const effort = capClaudeCatalogEffort(catalog, [opus], sources)[0]?.capabilities
@@ -417,6 +429,20 @@ describe("Claude model catalog", () => {
       maxLabel([perModel({ "claude-opus-5-5[1M]": "medium" })]),
       "Max (capped to Medium)",
     );
+    assert.strictEqual(maxLabel([perModel({ " OPUS[1m] ": "medium" })]), "Max (capped to Medium)");
+    // Other keys name the most specific model id they contain, so dated and provider-prefixed ids
+    // match while the catalog's dotted aliases and a less specific model id do not.
+    for (const key of [
+      "claude-opus-5-5-20260101",
+      "CLAUDE-OPUS-5-5-20260101[1m]",
+      "us.anthropic.claude-opus-5-5-v1:0",
+      "claude-opus-5-5-latest",
+    ]) {
+      assert.strictEqual(maxLabel([perModel({ [key]: "medium" })]), "Max (capped to Medium)", key);
+    }
+    for (const key of ["claude-opus-5.5", "opus-5.5", "opus-5-5", "opus [1m]", "claude-opus-5"]) {
+      assert.strictEqual(maxLabel([perModel({ [key]: "medium" })]), "Max", key);
+    }
     // Keys naming the same model keep the lowest cap, and a `max` key does not exempt it.
     assert.strictEqual(
       maxLabel([perModel({ opus: "max", "claude-opus-5-5": "low" })]),

apps/server/src/provider/ClaudeModelCatalog.ts

@@ -219,22 +219,49 @@ export interface ClaudeEffortCapSource {
 }
 
 const CLAUDE_1M_SUFFIX = "[1m]";
+const CLAUDE_CODE_FAMILY_ALIASES: ReadonlySet<string> = new Set([
+  "opus",
+  "sonnet",
+  "haiku",
+  "fable",
+]);
 
 /**
- * Keys `modelSettings` caps by canonical slug. Claude Code matches a key's aliases and `[1m]`
- * spelling case-insensitively, and keeps the lowest cap when several keys name one model.
+ * Names the model a `modelSettings` key caps the way Claude Code does, which is narrower than the
+ * catalog's aliases: only a family alias (optionally `[1m]`) resolves as an alias, and any other key
+ * names the most specific model id it contains, so `claude-opus-5-5-20260101` and Bedrock ids match
+ * while `claude-opus-5.5` matches nothing.
  */
+function resolveClaudeModelSettingsKey(
+  catalog: ClaudeModelCatalog,
+  key: string,
+): string | undefined {
+  const lowered = key.trim().toLowerCase();
+  const unsuffixed = lowered.endsWith(CLAUDE_1M_SUFFIX)
+    ? lowered.slice(0, -CLAUDE_1M_SUFFIX.length)
+    : lowered;
+  if (CLAUDE_CODE_FAMILY_ALIASES.has(unsuffixed)) {
+    return catalog.models.find(
+      (entry) => !entry.model.isCustom && entry.model.aliases?.includes(unsuffixed),
+    )?.model.slug;
+  }
+  let match: string | undefined;
+  for (const { model } of catalog.models) {
+    if (!model.isCustom && lowered.includes(model.slug) && model.slug.length > (match?.length ?? 0))
+      match = model.slug;
+  }
+  return match;
+}
+
+/** Keys `modelSettings` caps by canonical slug, keeping the lowest cap when several keys name one model. */
 function resolveClaudeModelMaxEffortLevels(
   catalog: ClaudeModelCatalog,
   levels: ReadonlyMap<string, ClaudeEffortLevel> | undefined,
 ): ReadonlyMap<string, ClaudeEffortLevel> {
   const resolved = new Map<string, ClaudeEffortLevel>();
   for (const [key, level] of levels ?? []) {
-    const lowered = key.trim().toLowerCase();
-    const slug = resolveClaudeModelSlug(
-      catalog,
-      lowered.endsWith(CLAUDE_1M_SUFFIX) ? lowered.slice(0, -CLAUDE_1M_SUFFIX.length) : lowered,
-    );
+    const slug = resolveClaudeModelSettingsKey(catalog, key);
+    if (!slug) continue;
     const current = resolved.get(slug);
     if (!current || claudeEffortRank(level) < claudeEffortRank(current)) resolved.set(slug, level);
   }