Populate OpenCode skills and subagents breakdowns (#557)

The Skills & Agents panel was always empty for OpenCode sessions even
when skills and subagents were used. buildAssistantCall (shared by the
OpenCode SQLite and file-based parsers, and Kilo Code) counted the
skill/task tool invocations but never read the skill name or subagent
type from the tool-call input, so the dedicated breakdowns had no names
to aggregate.

In OpenCode's part files the identifier lives in state.input: the skill
tool carries input.name and the task tool carries input.subagent_type.
Extract both in buildAssistantCall and surface them on
ParsedProviderCall.skills / .subagentTypes, then stop hard-coding
skills: [] in providerCallToTurn and providerCallToCachedCall so the
classifier's subCategory and the subagent breakdown receive the data.

Verified against real OpenCode data: the previously empty skills[] and
subagents[] now populate (pipeline-investigation, plan-spec, splunk, ...
and explore/general subagents).

Fixes #556

Co-authored-by: Kevin Addison <kevin.addison3@tesco.com>

src/parser.ts

@@ -1707,7 +1707,7 @@ function providerCallToTurn(call: ParsedProviderCall): ParsedTurn {
     costUSD: call.costUSD,
     tools,
     mcpTools: extractMcpTools(tools),
-    skills: [],
+    skills: call.skills ?? [],
     subagentTypes: call.subagentTypes ?? [],
     hasAgentSpawn: tools.includes('Agent'),
     hasPlanMode: tools.includes('EnterPlanMode'),
@@ -1746,7 +1746,7 @@ function providerCallToCachedCall(call: ParsedProviderCall): CachedCall {
     timestamp: call.timestamp,
     tools: call.tools,
     bashCommands: call.bashCommands,
-    skills: [],
+    skills: call.skills ?? [],
     subagentTypes: call.subagentTypes ?? [],
     deduplicationKey: call.deduplicationKey,
     project: call.project,

src/providers/session-message.ts

@@ -28,7 +28,7 @@ export type PartData = {
   type: string
   text?: string
   tool?: string
-  state?: { input?: { command?: string } }
+  state?: { input?: { command?: string; name?: string; subagent_type?: string } }
 }
 
 const toolNameMap: Record<string, string> = {
@@ -117,6 +117,18 @@ export function buildAssistantCall(opts: {
     .filter((p) => p.tool === 'bash' && typeof p.state?.input?.command === 'string')
     .flatMap((p) => extractBashCommands(p.state!.input!.command!))
 
+  // The skill/subagent name lives in the tool-call input, not the tool name, so
+  // the Skills & Agents breakdown needs these extracted alongside the tool list.
+  const skills = toolParts
+    .filter((p) => p.tool === 'skill' && typeof p.state?.input?.name === 'string')
+    .map((p) => p.state!.input!.name!)
+    .filter(Boolean)
+
+  const subagentTypes = toolParts
+    .filter((p) => p.tool === 'task' && typeof p.state?.input?.subagent_type === 'string')
+    .map((p) => p.state!.input!.subagent_type!)
+    .filter(Boolean)
+
   const model = data.modelID ?? data.model ?? 'unknown'
   let costUSD = calculateCost(
     model,
@@ -144,6 +156,8 @@ export function buildAssistantCall(opts: {
     costUSD,
     tools,
     bashCommands,
+    skills,
+    subagentTypes,
     timestamp: parseTimestamp(opts.timeCreatedMs),
     speed: 'standard',
     deduplicationKey: opts.dedupKey,

src/providers/types.ts

@@ -27,6 +27,9 @@ export type ParsedProviderCall = {
   // Subagent types spawned in this call (e.g. 'general-purpose'). Feeds the
   // Skills & Agents breakdown; optional since most providers don't expose it.
   subagentTypes?: string[]
+  // Skill names invoked in this call (e.g. 'commit'). Feeds the Skills & Agents
+  // breakdown; optional since most providers don't expose it.
+  skills?: string[]
   timestamp: string
   speed: 'standard' | 'fast'
   deduplicationKey: string

tests/providers/opencode-file.test.ts

@@ -138,6 +138,47 @@ describe('opencode file-based provider - parsing', () => {
     expect(c.deduplicationKey).toBe('opencode:ses_test1:msg_a')
   })
 
+  it('extracts skill names and subagent types from skill/task tool parts', async () => {
+    await writeSession({
+      messages: [{
+        id: 'msg_a',
+        data: {
+          role: 'assistant', modelID: 'gpt-5.3-codex-spark', cost: 0,
+          tokens: { input: 100, output: 20, reasoning: 0, cache: { read: 0, write: 0 } },
+          time: { created: 1 },
+        },
+        parts: [
+          { type: 'tool', tool: 'skill', state: { input: { name: 'commit' } } },
+          { type: 'tool', tool: 'task', state: { input: { description: 'find files', subagent_type: 'explore' } } },
+          { type: 'text', text: 'done' },
+        ],
+      }],
+    })
+    const calls = await parseAll()
+    expect(calls).toHaveLength(1)
+    const c = calls[0]!
+    expect(c.tools).toEqual(['Skill', 'Agent'])
+    expect(c.skills).toEqual(['commit'])
+    expect(c.subagentTypes).toEqual(['explore'])
+  })
+
+  it('leaves skills and subagentTypes empty when no skill/task parts are present', async () => {
+    await writeSession({
+      messages: [{
+        id: 'msg_a',
+        data: {
+          role: 'assistant', modelID: 'gpt-5.3-codex-spark', cost: 0,
+          tokens: { input: 100, output: 20, reasoning: 0, cache: { read: 0, write: 0 } },
+          time: { created: 1 },
+        },
+        parts: [{ type: 'tool', tool: 'bash', state: { input: { command: 'ls' } } }],
+      }],
+    })
+    const calls = await parseAll()
+    expect(calls[0]!.skills).toEqual([])
+    expect(calls[0]!.subagentTypes).toEqual([])
+  })
+
   it('skips an errored or empty assistant turn (all-zero tokens, no parts)', async () => {
     await writeSession({
       messages: [{