fix: dispatch tool metadata on category for cross-agent consistency (wesm#116)

## Summary
- `extractToolParamMeta` now dispatches on normalized `category` (Read,
Bash, Edit, etc.) instead of raw `tool_name`, so Gemini tools
(`run_command`, `read_file`, `grep_search`, etc.) render with the same
metadata tags as their Claude equivalents
- Adds `cmd` meta tag for Bash category showing first line of command,
truncated to 80 chars
- Normalizes param name lookups across agents (`file_path`/`path`,
`pattern`/`query`, `command`/`cmd`)
- Simplifies ToolBlock callsite: single `extractToolParamMeta(toolName,
params, category)` call replaces the
try-category-then-fallback-to-toolName pattern

Follow-up to wesm#114. Missing ABOUTME file brief for `gemini.go` will be
addressed in a separate PR.

## Test plan
- [ ] Verify Gemini tool calls show metadata tags (file path, command,
pattern) in collapsed ToolBlock header
- [ ] Verify Claude tool calls still render identically (no regression)
- [ ] `npx vitest run src/lib/utils/tool-params.test.ts` — 57 tests pass

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Co-authored-by: Wes McKinney <wesmckinn+git@gmail.com>

Author: 3 people

frontend/src/lib/components/content/ToolBlock.svelte

@@ -103,9 +103,7 @@
   /** Extract metadata tags for common tool types */
   let toolParamMeta = $derived.by(() => {
     if (!inputParams || !toolCall) return null;
-    const cat = toolCall.category || null;
-    const result = cat ? extractToolParamMeta(cat, inputParams) : null;
-    return result ?? extractToolParamMeta(toolCall.tool_name, inputParams);
+    return extractToolParamMeta(toolCall.tool_name, inputParams, toolCall.category);
   });
 
   /** Combined metadata for any tool type */

frontend/src/lib/utils/tool-params.test.ts

@@ -109,20 +109,33 @@ describe("extractToolParamMeta", () => {
     ]);
   });
 
-  it("extracts Bash description", () => {
+  it("extracts Bash description and cmd", () => {
     const meta = extractToolParamMeta("Bash", {
       command: "npm test",
       description: "Run test suite",
     });
     expect(meta).toEqual([
       { label: "description", value: "Run test suite" },
+      { label: "cmd", value: "npm test" },
     ]);
   });
 
-  it("returns null for Bash without description", () => {
-    expect(
-      extractToolParamMeta("Bash", { command: "ls" }),
-    ).toBeNull();
+  it("extracts Bash cmd without description", () => {
+    const meta = extractToolParamMeta("Bash", {
+      command: "ls -la",
+    });
+    expect(meta).toEqual([
+      { label: "cmd", value: "ls -la" },
+    ]);
+  });
+
+  it("shows only first line of multiline Bash command", () => {
+    const meta = extractToolParamMeta("Bash", {
+      command: "echo hello\necho world",
+    });
+    expect(meta).toEqual([
+      { label: "cmd", value: "echo hello" },
+    ]);
   });
 
   it("extracts Skill name", () => {
@@ -134,6 +147,50 @@ describe("extractToolParamMeta", () => {
     ]);
   });
 
+  it("dispatches on category for Gemini read_file", () => {
+    const meta = extractToolParamMeta(
+      "read_file",
+      { file_path: "/src/main.go" },
+      "Read",
+    );
+    expect(meta).toEqual([
+      { label: "file", value: "/src/main.go" },
+    ]);
+  });
+
+  it("dispatches on category for Gemini run_command", () => {
+    const meta = extractToolParamMeta(
+      "run_command",
+      { command: "go test ./..." },
+      "Bash",
+    );
+    expect(meta).toEqual([
+      { label: "cmd", value: "go test ./..." },
+    ]);
+  });
+
+  it("dispatches on category for Gemini grep_search", () => {
+    const meta = extractToolParamMeta(
+      "grep_search",
+      { query: "TODO" },
+      "Grep",
+    );
+    expect(meta).toEqual([
+      { label: "pattern", value: "TODO" },
+    ]);
+  });
+
+  it("falls back to toolName when category is empty string", () => {
+    const meta = extractToolParamMeta(
+      "Read",
+      { file_path: "/src/app.ts" },
+      "",
+    );
+    expect(meta).toEqual([
+      { label: "file", value: "/src/app.ts" },
+    ]);
+  });
+
   it("returns null for unknown tool with no matching params", () => {
     expect(
       extractToolParamMeta("CustomTool", { foo: "bar" }),

frontend/src/lib/utils/tool-params.ts

@@ -12,15 +12,19 @@ export function truncate(s: string, max: number): string {
 type Params = Record<string, unknown>;
 
 /** Extract metadata tags for common tool types.
+ *  Dispatches on normalized category so all agents (Claude,
+ *  Gemini, Codex, etc.) render consistently.
  *  Returns null for Task/TaskCreate/TaskUpdate (handled separately). */
 export function extractToolParamMeta(
   toolName: string,
   params: Params,
+  category?: string,
 ): MetaTag[] | null {
   const skip = ["Task", "TaskCreate", "TaskUpdate"];
   if (skip.includes(toolName)) return null;
+  const cat = category || toolName;
   const meta: MetaTag[] = [];
-  if (toolName === "Read") {
+  if (cat === "Read") {
     const filePath = params.file_path ?? params.path;
     if (filePath)
       meta.push({
@@ -42,7 +46,7 @@ export function extractToolParamMeta(
         label: "pages",
         value: String(params.pages),
       });
-  } else if (toolName === "Edit") {
+  } else if (cat === "Edit") {
     const filePath = params.file_path ?? params.path ?? params.filePath;
     if (filePath)
       meta.push({
@@ -51,18 +55,19 @@ export function extractToolParamMeta(
       });
     if (params.replace_all)
       meta.push({ label: "mode", value: "replace_all" });
-  } else if (toolName === "Write") {
+  } else if (cat === "Write") {
     const filePath = params.file_path ?? params.path;
     if (filePath)
       meta.push({
         label: "file",
         value: truncate(String(filePath), 80),
       });
-  } else if (toolName === "Grep") {
-    if (params.pattern)
+  } else if (cat === "Grep") {
+    const pattern = params.pattern ?? params.query;
+    if (pattern)
       meta.push({
         label: "pattern",
-        value: truncate(String(params.pattern), 60),
+        value: truncate(String(pattern), 60),
       });
     if (params.path)
       meta.push({
@@ -76,7 +81,7 @@ export function extractToolParamMeta(
         label: "mode",
         value: String(params.output_mode),
       });
-  } else if (toolName === "Glob") {
+  } else if (cat === "Glob") {
     if (params.pattern)
       meta.push({
         label: "pattern",
@@ -87,17 +92,26 @@ export function extractToolParamMeta(
         label: "path",
         value: truncate(String(params.path), 80),
       });
-  } else if (toolName === "Bash") {
+  } else if (cat === "Bash") {
     if (params.description)
       meta.push({
         label: "description",
         value: truncate(String(params.description), 80),
       });
-  } else if (toolName === "Skill") {
-    if (params.skill)
+    const cmd = params.command ?? params.cmd;
+    if (cmd) {
+      const firstLine = String(cmd).split("\n")[0];
+      meta.push({
+        label: "cmd",
+        value: truncate(firstLine, 80),
+      });
+    }
+  } else if (toolName === "Skill" || toolName === "skill") {
+    const skill = params.skill ?? params.name;
+    if (skill)
       meta.push({
         label: "skill",
-        value: String(params.skill),
+        value: String(skill),
       });
   }
   return meta.length ? meta : null;