# Agent Market (demo) A marketplace page that an AI agent drives. The landing page loads like a normal site, and a chat popup lets the agent decide what the page shows. The agent answers with **UI actions** picked from a fixed set of components, and the browser renders them. People and other AI agents can list, buy and sell products or services. > **TEST DEMO ONLY.** Every listing is fake test data. Payments go through a mock, test-mode > provider that only accepts test card numbers. No real money moves. ## How it works ``` browser (React SPA) ─────/api/chat──▶ tiny server ──▶ free hosted LLMs (OpenAI-compatible) ▲ renders UI actions │ then the local model on this box (llama-server) │ ├── /api/payments/* ── mock test-mode provider ── signed webhook └── card form posts straight ────────┘ to the payment endpoint (never to the LLM) other AI agents ──/api/actions (same actions)──▶ same server ``` The server stays small on purpose. It does three things: 1. **LLM proxy.** It keeps the API key on the server, sends the chat plus a component and tool schema to the model, runs the model's tool calls (search, create listing, start checkout, start or complete a cash deal), then checks and fills in the UI actions it returns. Unknown components get dropped, and listing ids are resolved against the store, so the model can't make up items. 2. **Payments (test mode).** `POST /api/payments/{intent}/confirm` hands the card to a mock provider. The provider decides the outcome and sends an **HMAC-signed webhook** to `/api/payments/webhook`, which records the order. The server rejects any card that isn't on the test-card list. 3. **Agent API.** `POST /api/actions` exposes the same actions to outside agents. They're described in `/agent.json` and `/openapi.json`. ### UI components the agent can use `show_hero`, `show_cards`, `show_listing_form`, `show_compare`, `show_checkout`, `show_cash_meetup`, `show_receipt`, `toast`, `clear_panel`. ### Look and layout (agent-controlled, per visitor) The agent can restyle the whole page from chat with one action, `set_theme`. Its payload is a JSON theme spec: design tokens applied as CSS variables. The model never sends raw HTML or JS. The server checks every value (`market/theme.py`), and the browser applies the result (`web/src/theme/engine.ts`). | Area | Spec keys | |---|---| | Background | `background.kind` solid/gradient/pattern (dots, grid, stripes, diagonal, checks, waves)/image (only images.unsplash.com, picsum.photos, upload.wikimedia.org), `colors`, `angle` | | Colours | `mode` light/dark, `palette.{bg,surface,card,text,muted,accent,border}` | | Type | `font`, `headingFont` (19 curated web-safe and Google fonts), `fontScale` 0.75 to 1.75 | | Shape and spacing | `radius` 0 to 32, `density` compact/normal/comfy, `cardStyle` flat/outlined/elevated/glass | | Layout | `layout` grid/list, `columns` 0 to 6, `sections.order` / `sections.hidden` (hero, chips, bullets, results, footer) | | Copy | `copy.{logo,headline,subhead,footer,chips[],bullets[]}` | | Chat | `chat.{position,width,height,bg,accent,text}` | | Motion | `animations` on/off | | Presets | `preset`: retro, minimal, neon, pastel, high contrast, sunset, ocean, plus `reset` | | Escape hatch | `customCss`, sanitised and scoped (details below) | **Per visitor.** The theme lives in the browser's `localStorage`. The server never stores it, so one visitor's restyle never changes the page for anyone else. **Reset look** in the header, or saying "reset the look" in chat, restores the default. **Guardrails.** - `customCss` is sanitised before it's applied: - The server drops `@import` and every other at-rule, `expression()`, `javascript:`, `behavior`, HTML, `!important`, custom properties, and negative margins. - It neutralises `url()` pointing anywhere outside the image allowlist. - Only an allowlist of properties survives. Positioning, z-index, `content` and transforms aren't on it. - Rules are scoped under `#page`, and the browser checks them again. - The CSS uses cascade layers in the order `base < user < protected`. The TEST DEMO banner, the agent badge, and the checkout, cash and receipt panels (fee lines, totals, the test-card notice and the card inputs) live in `protected`. No theme can hide, recolour or shrink them. - Protected panels use the theme's surface colour as a solid fill, with black or white text, whichever contrasts more, so they always clear 4.5:1. The banner and badge use fixed high-contrast colours. - Text sitting directly on the page background switches to readable ink. If no ink clears 4.5:1 against every gradient stop, it gets a scrim behind it. - **Page text.** The logo (top-left brand text), headline, subtitle, footer, quick-action buttons and bullets are editable through `copy`. The prompt maps where each slot is ("top left" = `copy.logo`, title, subtitle, footer, ...) and includes the visitor's current page text (`PAGE_TEXT`, from `market/copyedit.py`), so "replace agent market to new internet on the top left corner" becomes `{"copy":{"logo":"New Internet"}}`. There is no rule-based text or look editing: every typed request is answered by a model (see below). ### Fees - **Online payment:** a facilitation fee of `AGENT_MARKET_FEE_BPS` basis points. The default is 500, which is 5%. The buyer pays it on top of the price, the seller gets the full price, and checkout shows the fee on its own line. - **Cash in person:** no fee. The site only connects buyer and seller and records the deal. ### Test cards (mock provider) | Card | Result | |---|---| | 4242 4242 4242 4242 | succeeds | | 4000 0000 0000 0002 | declined | | 4000 0000 0000 9995 | insufficient funds | | anything else | refused (`not_a_test_card`) | ## LLM configuration The server talks to any OpenAI-compatible `/chat/completions` endpoint, and the key stays on the server: it never goes to the browser, never into the repo, and never into a URL. | Variable | Meaning | |---|---| | `AGENT_MARKET_LLM_API_KEY_FILE` | path to a file holding the key (preferred), e.g. `~/.config/agent-market/openrouter.key` (mode 600) | | `AGENT_MARKET_LLM_API_KEY` | the key itself, if a file can't be used | | `AGENT_MARKET_LLM_BASE_URL` | e.g. `https://openrouter.ai/api/v1` | | `AGENT_MARKET_LLM_MODELS` | comma-separated fallback chain, tried in order | | `AGENT_MARKET_LLM_TIMEOUT` / `_BUDGET` | hard cap per model attempt (12 s) and for the whole chain (28 s) | | `AGENT_MARKET_LLM_COOLDOWN` | how long a model that returned 429 gets skipped (60 s) | | `AGENT_MARKET_CHAT_RPM` / `_BURST` | per-IP token bucket on `/api/chat` turns that reach the LLM (12/min, burst 6). Deterministic UI events aren't limited. `CF-Connecting-IP` is trusted only from loopback, i.e. the tunnel. | `deploy.sh` loads `~/.config/agent-market/llm.env` and `~/.config/agent-market/.env` if they exist. Both sit outside the repo. The box runs OpenRouter free models: `nvidia/nemotron-3-super-120b-a12b:free` → `apodex/apodex-1.1-mini:free` → `google/gemma-4-31b-it:free` → **local `gemma3:4b`** That is the whole chain. There are no keyword rules for typed messages. The order came from a benchmark of natural-language prompts, scored on valid UI actions and latency. In that run: - **nemotron-3-super**: 8/8 valid, about 2–3 s. - **apodex-1.1-mini**: 6/6 valid, about 2 s. - **gemma-4-31b and gemma-4-26b**: rate-limited upstream (429). - **inkling**: 403, because it's limited to agentic harnesses. - **nemotron-3.5-lightning**: 24–55 s, and returned non-JSON. If a model returns 429, it times out, or it returns invalid JSON, the server moves on to the next model in the chain. When every model fails (or none is configured), the reply is an honest **"The assistant is busy, please try again in a moment."** with a **Retry** button that resends the same message (`agent: "unavailable"`, no actions; the badge says `AI: busy`). Typed messages never get rule-based answers. The header badge shows the model that answered. ### Local model (last link of the chain) A small model runs on the box with llama.cpp's `llama-server` (the build that ships inside Ollama v0.40.1 under `~/ollama/lib/ollama/`; any llama.cpp build works). The server tries it after the hosted chain, through the same OpenAI-compatible endpoint (`/v1/chat/completions`), with no key. **It gets its own compact prompt**, because CPU prefill costs about 13 ms per prompt token: - `LOCAL_PROMPT` + `_local_system_prompt()`: a terse action list, a dozen one-line examples, the default page text and a one-line-per-listing catalog with short refs (`L1`, `L2`, ...; small models miscopy 8-hex ids, the server maps refs back) and dollar prices. About 1.2k tokens instead of about 3k, and it is the same for every visitor, so llama-server's prompt cache always hits. It only changes when the catalog does (the primer re-warms it then). - `_local_user()`: the per-visitor part (a few dozen tokens): the visitor's look overrides if any, a `MATCHING LISTINGS` hint (listings sharing a word with the message, within any stated budget), and the message. - A JSON GBNF grammar, `max_tokens` 200, no chat history and no tool round. Over-budget picks are dropped when some fit. Measured on the demo catalog (12 typical prompts, warm): 12/12 correct, median 5.9 s, max 7.7 s. A turn right after a catalog change, before the primer runs, pays about 13 s of prefill once. | Variable | Meaning | |---|---| | `AGENT_MARKET_LOCAL_LLM_URL` | e.g. `http://127.0.0.1:11434/v1` (loopback only) | | `AGENT_MARKET_LOCAL_LLM_MODEL` | e.g. `gemma3:4b` (the server's `--alias`) | | `AGENT_MARKET_LOCAL_LLM_TIMEOUT` / `_MIN` | its own cap (45 s; CPU inference is slower) and the minimum it always gets (25 s) | | `AGENT_MARKET_LLM_TOTAL_BUDGET` | hosted chain + local model per turn (60 s); the local model gets `min(45, max(25, 60 - time already spent))` | | `AGENT_MARKET_LOCAL_LLM_CONCURRENCY` | 2 = one running + one queued; more simultaneous turns get the busy reply instead of waiting | | `AGENT_MARKET_LOCAL_LLM_HISTORY` | chat turns sent to the local model (0) | | `AGENT_MARKET_LOCAL_LLM_MAX_TOKENS` | output cap for the local model (200; replies are one sentence + one action) | | `AGENT_MARKET_LOCAL_LLM_PRIME` | 1 = warm the prompt cache in the background (see below) | `deploy.sh` loads these from `~/.config/agent-market/local-llm.env`. The behaviour: - **Quota stop.** When OpenRouter reports the daily free quota is used up, every hosted model is parked until the reset time and turns go **straight to the local model**, with no hosted calls in between. The stop is saved in the data directory (`llm_quota.json`, keyed by the base URL, capped at 36 h), so a restart doesn't spend a call to rediscover it. - **Badge.** It honestly shows `Local model (gemma3:4b)` when the local model answered (chat header: `Local model · gemma3:4b · 8.2s`), and also on page load while the hosted quota is used up. - **Prompt cache.** The first call with a new prompt prefix processes about 2.4k prompt tokens on the CPU (about 30–40 s). A background primer sends the current prompt once (1 output token) at start-up, whenever the catalog changes, and after the model server restarts (detected from llama-server's `/metrics` counter). Otherwise it only reads `/metrics` every 30 s, so an idle server stays at 0% CPU. `--swa-full` keeps Gemma's sliding-window layers reusable, so a warm turn only processes the new tokens (about 0.3 s). `--cache-ram 1024` keeps a few prompt states (demo and staging) in RAM. - **Running it.** `ops/local-llm-watchdog.sh --ensure` (idempotent; `deploy.sh` calls it) starts a private copy of the watchdog under `~/llm/`. It keeps `llama-server` on `127.0.0.1:11434` only, restarts it if it exits (backing off to 30 s if it keeps crashing) or fails 3 health checks 15 s apart, and rotates its log. Stop it with `kill $(cat ~/llm/watchdog.pid)`. Lean flags so the rest of the box keeps headroom: text weights only (`--no-mmproj`, the 0.8 GB vision projector is never loaded), mmapped and not repacked (`--no-repack`, no second copy of the weights), `-c 6144 -np 1`, q8 KV cache, flash attention, `-t 6 -tb 6` at `nice 10`, `--poll 0` (threads sleep when idle). Overrides go in `~/.config/agent-market/local-llm-server.env`. Model file: the gemma3:4b Q4_K_M text GGUF (2.4 GB), linked as `~/llm/gemma3-4b-it-Q4_K_M.gguf`. - **Resources (measured on this box: 8 vCPU, no GPU, 16 GB RAM).** Idle: 0% CPU, 2.9 GB RSS, of which 0.6 GB is private and 2.4 GB is the mmapped model file (clean page cache the kernel can reclaim). While answering: about 6 cores at nice 10 for 4–8 s, RSS unchanged. - **Latency (real chain, handle_chat, warm cache, compact prompt).** Exact logo phrase 4.5 s, look edits 4–6 s, search 6 s, compare 6 s, checkout 4 s, cash meetup 4.5 s, prefilled listing form 7–8 s. Cold prefill of the 1.2k-token prompt: about 13 s, once per catalog change. The single slot is shared by demo and staging, so a staging test run makes a demo visitor wait for at most one other reply. - **Model choice.** Benchmarked on this box with the real prompt and catalog: | model | correct | warm latency | notes | |---|---|---|---| | **gemma3:4b** (chosen) | 18/18 (compact prompt), 15/15 (Ollama, long prompt) | 4–8 s, cold about 18 s | 2.9 GB RSS | | qwen2.5:3b | 7/15 | 3–8 s | dropped actions, invented ids, flat payloads | | phi4-mini | 4/5 | 10–25 s | missed the logo edit | | qwen3:4b (no think) | 4/5 | 12–22 s | slow, missed the logo edit | | llama3.2:3b | 1/5 | 4–8 s | mostly empty plans | | qwen2.5:1.5b | 0/5 | 3–6 s | no usable plans | 7B models were left out: they need about 5 GB more RAM, and on this CPU they would be about 2–3x slower. Ollama itself was dropped in favour of running `llama-server` directly: Ollama loaded the vision projector, a 16k context with 2 slots and an 8 GiB prompt cache, which grew to about 10 GB RSS. **Free text goes to the LLM. Structured UI events stay deterministic.** Button clicks, form submits and payment results each have exactly one outcome, so the server handles them deterministically. That keeps them instant and saves free-tier quota. The landing view doesn't call the model either. Set `AGENT_MARKET_LLM_EVENTS=1` to send events to the LLM as well. With no model configured at all, clicks, forms and payments still work, and typed messages get the busy reply. ## Frontend (React + Vite + TypeScript) The page is a React single-page app in `web/`. The Python server and API are unchanged, except that `/` now serves the built `static/dist/index.html` and `/static/dist/assets/*` serves the hashed JS/CSS bundles. ``` web/ index.html # declares `@layer base, user, protected;` first, then