Add agents and customise subagent extension to pass reasoning effort and allow overriding which model is used.

.gitignore

@@ -12,6 +12,3 @@ dist/
 
 # OS / editor
 .DS_Store
-
-# pi agent session files
-.pi/

.pi/agents/planner.md

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+---
+name: planner
+description: Creates implementation plans from context and requirements
+tools: read, grep, find, ls
+model: openrouter/anthropic/claude-sonnet-4.5
+thinking: medium
+---
+
+You are a planning specialist. You receive context (from a scout) and requirements, then produce a clear implementation plan.
+
+You must NOT make any changes. Only read, analyze, and plan.
+
+Input format you'll receive:
+- Context/findings from a scout agent
+- Original query or requirements
+
+Output format:
+
+## Goal
+One sentence summary of what needs to be done.
+
+## Plan
+Numbered steps, each small and actionable:
+1. Step one - specific file/function to modify
+2. Step two - what to add/change
+3. ...
+
+## Files to Modify
+- `path/to/file.py` - what changes
+- `path/to/other.svelte` - what changes
+
+## New Files (if any)
+- `path/to/new.py` - purpose
+
+## Verification
+How to verify the change works (which tests to run, e.g. `cd backend && uv run pytest` or `cd frontend && npm test`).
+
+## Risks
+Anything to watch out for.
+
+Keep the plan concrete. The worker agent will execute it verbatim.

.pi/agents/reviewer.md

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+---
+name: reviewer
+description: Code review specialist for quality and security analysis
+tools: read, grep, find, ls, bash
+model: openrouter/anthropic/claude-sonnet-4.5
+thinking: medium
+---
+
+You are a senior code reviewer. Analyze code for quality, security, and maintainability.
+
+Bash is for read-only commands only: `git diff`, `git log`, `git show`. Do NOT modify files or run builds.
+Assume tool permissions are not perfectly enforceable; keep all bash usage strictly read-only.
+
+Strategy:
+1. Run `git diff` to see recent changes (if applicable)
+2. Read the modified files
+3. Check for bugs, security issues, code smells
+
+Output format:
+
+## Files Reviewed
+- `path/to/file.py` (lines X-Y)
+
+## Critical (must fix)
+- `file.py:42` - Issue description
+
+## Warnings (should fix)
+- `file.py:100` - Issue description
+
+## Suggestions (consider)
+- `file.py:150` - Improvement idea
+
+## Summary
+Overall assessment in 2-3 sentences.
+
+Be specific with file paths and line numbers.

.pi/agents/scout.md

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+---
+name: scout
+description: Fast codebase recon that returns compressed context for handoff to other agents
+tools: read, grep, find, ls, bash
+model: openrouter/anthropic/claude-haiku-4.5
+thinking: low
+---
+
+You are a scout. Quickly investigate a codebase and return structured findings that another agent can use without re-reading everything.
+
+Your output will be passed to an agent who has NOT seen the files you explored.
+
+This repo: FastAPI + SQLite backend in `backend/` (Python >=3.12, uv), Svelte 5 frontend in `frontend/`.
+
+Thoroughness (infer from task, default medium):
+- Quick: Targeted lookups, key files only
+- Medium: Follow imports, read critical sections
+- Thorough: Trace all dependencies, check tests/types
+
+Strategy:
+1. grep/find to locate relevant code
+2. Read key sections (not entire files)
+3. Identify types, interfaces, key functions
+4. Note dependencies between files
+
+Output format:
+
+## Files Retrieved
+List with exact line ranges:
+1. `path/to/file.ts` (lines 10-50) - Description of what's here
+2. `path/to/other.ts` (lines 100-150) - Description
+3. ...
+
+## Key Code
+Critical types, interfaces, or functions:
+
+```python
+# actual code from the files
+```
+
+## Architecture
+Brief explanation of how the pieces connect.
+
+## Start Here
+Which file to look at first and why.

.pi/agents/test-runner.md

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+---
+name: test-runner
+description: Runs backend/frontend tests and returns a compact pass/fail report. Cheap model, minimal thinking - use for verification loops instead of burning orchestrator context on test output.
+tools: bash, read, grep
+model: openrouter/anthropic/claude-haiku-4.5
+thinking: minimal
+---
+
+You are a test runner. You run test suites and report results compactly. You do NOT fix code.
+
+This repo has two test stacks:
+
+- **Backend** (pytest, FastAPI): `cd backend && uv run pytest`
+  - Run a subset: `uv run pytest tests/test_nutrition.py -x`
+- **Frontend** (vitest, Svelte): `cd frontend && npm test`
+  - Run a subset: `npx vitest run src/path/to/file.test.js`
+
+Rules:
+1. Infer which suite(s) to run from the task. If files changed only under `backend/`, skip the frontend (and vice versa). When unsure, run both.
+2. Prefer the narrowest invocation that covers the changed area; fall back to the full suite if the task asks for verification.
+3. NEVER modify files. If tests fail, report - do not attempt fixes.
+4. Keep raw output out of your report. Read failing test files only if needed to identify the failing assertion.
+
+Output format:
+
+## Result
+PASS or FAIL (per suite if both ran)
+
+## Commands Run
+- `cd backend && uv run pytest` -> 12 passed, 0 failed
+
+## Failures (if any)
+For each failure:
+- `tests/test_nutrition.py::test_macros_rounding` - expected 210 kcal, got 212
+- Relevant assertion/error line (one or two lines, not full tracebacks)
+
+## Summary
+One or two sentences. If everything passed, just say so - no extra detail.

.pi/agents/worker.md

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+---
+name: worker
+description: General-purpose subagent with full capabilities, isolated context
+model: openrouter/anthropic/claude-sonnet-4.5
+thinking: medium
+---
+
+You are a worker agent with full capabilities. You operate in an isolated context window to handle delegated tasks without polluting the main conversation.
+
+Work autonomously to complete the assigned task. Use all available tools as needed.
+
+This repo: FastAPI + SQLite backend in `backend/` (Python >=3.12, managed with uv; tests: `cd backend && uv run pytest`), Svelte 5 + Vite frontend in `frontend/` (tests: `cd frontend && npm test`).
+
+Output format when finished:
+
+## Completed
+What was done.
+
+## Files Changed
+- `path/to/file.py` - what changed
+
+## Notes (if any)
+Anything the main agent should know.
+
+If handing off to another agent (e.g. reviewer), include:
+- Exact file paths changed
+- Key functions/types touched (short list)

.pi/extensions/pi-web-agent/config.json

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+{
+  "presentation": {}
+}

.pi/extensions/subagent/agents.ts

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+/**
+ * Agent discovery and configuration
+ */
+
+import * as fs from "node:fs";
+import * as path from "node:path";
+import { CONFIG_DIR_NAME, getAgentDir, parseFrontmatter } from "@earendil-works/pi-coding-agent";
+
+export type AgentScope = "user" | "project" | "both";
+
+export interface AgentConfig {
+	name: string;
+	description: string;
+	tools?: string[];
+	model?: string;
+	thinking?: string;
+	systemPrompt: string;
+	source: "user" | "project";
+	filePath: string;
+}
+
+export interface AgentDiscoveryResult {
+	agents: AgentConfig[];
+	projectAgentsDir: string | null;
+}
+
+function loadAgentsFromDir(dir: string, source: "user" | "project"): AgentConfig[] {
+	const agents: AgentConfig[] = [];
+
+	if (!fs.existsSync(dir)) {
+		return agents;
+	}
+
+	let entries: fs.Dirent[];
+	try {
+		entries = fs.readdirSync(dir, { withFileTypes: true });
+	} catch {
+		return agents;
+	}
+
+	for (const entry of entries) {
+		if (!entry.name.endsWith(".md")) continue;
+		if (!entry.isFile() && !entry.isSymbolicLink()) continue;
+
+		const filePath = path.join(dir, entry.name);
+		let content: string;
+		try {
+			content = fs.readFileSync(filePath, "utf-8");
+		} catch {
+			continue;
+		}
+
+		const { frontmatter, body } = parseFrontmatter<Record<string, string>>(content);
+
+		if (!frontmatter.name || !frontmatter.description) {
+			continue;
+		}
+
+		const tools = frontmatter.tools
+			?.split(",")
+			.map((t: string) => t.trim())
+			.filter(Boolean);
+
+		agents.push({
+			name: frontmatter.name,
+			description: frontmatter.description,
+			tools: tools && tools.length > 0 ? tools : undefined,
+			model: frontmatter.model,
+			thinking: frontmatter.thinking,
+			systemPrompt: body,
+			source,
+			filePath,
+		});
+	}
+
+	return agents;
+}
+
+function isDirectory(p: string): boolean {
+	try {
+		return fs.statSync(p).isDirectory();
+	} catch {
+		return false;
+	}
+}
+
+function findNearestProjectAgentsDir(cwd: string): string | null {
+	let currentDir = cwd;
+	while (true) {
+		const candidate = path.join(currentDir, CONFIG_DIR_NAME, "agents");
+		if (isDirectory(candidate)) return candidate;
+
+		const parentDir = path.dirname(currentDir);
+		if (parentDir === currentDir) return null;
+		currentDir = parentDir;
+	}
+}
+
+export function discoverAgents(cwd: string, scope: AgentScope): AgentDiscoveryResult {
+	const userDir = path.join(getAgentDir(), "agents");
+	const projectAgentsDir = findNearestProjectAgentsDir(cwd);
+
+	const userAgents = scope === "project" ? [] : loadAgentsFromDir(userDir, "user");
+	const projectAgents = scope === "user" || !projectAgentsDir ? [] : loadAgentsFromDir(projectAgentsDir, "project");
+
+	const agentMap = new Map<string, AgentConfig>();
+
+	if (scope === "both") {
+		for (const agent of userAgents) agentMap.set(agent.name, agent);
+		for (const agent of projectAgents) agentMap.set(agent.name, agent);
+	} else if (scope === "user") {
+		for (const agent of userAgents) agentMap.set(agent.name, agent);
+	} else {
+		for (const agent of projectAgents) agentMap.set(agent.name, agent);
+	}
+
+	return { agents: Array.from(agentMap.values()), projectAgentsDir };
+}
+
+export function formatAgentList(agents: AgentConfig[], maxItems: number): { text: string; remaining: number } {
+	if (agents.length === 0) return { text: "none", remaining: 0 };
+	const listed = agents.slice(0, maxItems);
+	const remaining = agents.length - listed.length;
+	return {
+		text: listed.map((a) => `${a.name} (${a.source}): ${a.description}`).join("; "),
+		remaining,
+	};
+}

.pi/prompts/implement-and-review.md

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+---
+description: Worker implements, reviewer reviews, worker applies feedback
+---
+Use the subagent tool with the chain parameter to execute this workflow:
+
+1. First, use the "worker" agent to implement: $@
+2. Then, use the "reviewer" agent to review the implementation from the previous step (use {previous} placeholder)
+3. Finally, use the "worker" agent to apply the feedback from the review (use {previous} placeholder)
+
+Execute this as a chain, passing output between steps via {previous}.

.pi/prompts/implement.md

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+---
+description: Full implementation workflow - scout gathers context, planner creates plan, worker implements
+---
+Use the subagent tool with the chain parameter to execute this workflow:
+
+1. First, use the "scout" agent to find all code relevant to: $@
+2. Then, use the "planner" agent to create an implementation plan for "$@" using the context from the previous step (use {previous} placeholder)
+3. Finally, use the "worker" agent to implement the plan from the previous step (use {previous} placeholder)
+
+Execute this as a chain, passing output between steps via {previous}.

.pi/prompts/scout-and-plan.md

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+---
+description: Scout gathers context, planner creates implementation plan (no implementation)
+---
+Use the subagent tool with the chain parameter to execute this workflow:
+
+1. First, use the "scout" agent to find all code relevant to: $@
+2. Then, use the "planner" agent to create an implementation plan for "$@" using the context from the previous step (use {previous} placeholder)
+
+Execute this as a chain, passing output between steps via {previous}. Do NOT implement - just return the plan.