diff --git a/desktop/src-tauri/assets/card_template.png b/desktop/src-tauri/assets/card_template.png
new file mode 100644
index 000000000..2225d1d44
Binary files /dev/null and b/desktop/src-tauri/assets/card_template.png differ
diff --git a/desktop/src-tauri/src/commands/personas/card.rs b/desktop/src-tauri/src/commands/personas/card.rs
new file mode 100644
index 000000000..f37e60aab
--- /dev/null
+++ b/desktop/src-tauri/src/commands/personas/card.rs
@@ -0,0 +1,526 @@
+//! `mint_agent_card` / `save_agent_card` Tauri commands — Agent Trading Cards.
+//!
+//! Mints a collectible trading-card PNG for an agent via one OpenAI Responses
+//! API call (designer model + native `image_generation` tool), then embeds the
+//! agent's `buzz_agent_snapshot` manifest through the existing snapshot
+//! encoder so the card IS an importable `.agent.png`.
+//!
+//! Boundary rules (agreed with Wren, buzz-agent-trading-cards thread):
+//! - Snapshot construction/injection reuses `agent_snapshot.rs` — cards
+//!   inherit manifest-v1 behavior, exclusions, and size checks. No card-only
+//!   wire format exists.
+//! - Memory exclusion is structural: the manifest is built with
+//!   `MemoryLevel::None`; the encoder itself rejects `none` + entries.
+//! - The 10 MiB `.agent.png` ceiling is enforced on the FINAL bytes (after
+//!   resize + chunk injection) via `validate_snapshot_encode_size`.
+//! - Round-trip verification decodes the final bytes and compares the logical
+//!   manifest before anything is returned to the frontend.
+//! - The API key is resolved through the same env layering the agent runtime
+//!   uses (global config < persona < agent record) and never leaves Rust.
+//!   It is never logged.
+
+use base64::{engine::general_purpose::STANDARD, Engine as _};
+use serde::Serialize;
+use tauri::{AppHandle, State};
+
+use super::super::export_util::save_bytes_with_dialog;
+use super::snapshot::{resolve_from_lists, validate_snapshot_encode_size};
+use crate::{
+    app_state::AppState,
+    managed_agents::{
+        agent_snapshot::{
+            build_snapshot, decode_avatar_data_url, decode_snapshot_png, encode_snapshot_png,
+            MemoryLevel,
+        },
+        load_agent_definitions, load_global_agent_config, load_managed_agents, load_personas,
+    },
+};
+
+/// The Buzz card frame template — Tyler's gold-honeycomb base. Generation
+/// input only: it never participates in the snapshot manifest, PNG chunk,
+/// import decoder, or attachment validation. Embedded at compile time for
+/// deterministic packaging (see `card_template_decodes` test).
+const CARD_TEMPLATE_PNG: &[u8] = include_bytes!("../../../assets/card_template.png");
+
+/// Designer model driving copy + art direction.
+const DESIGNER_MODEL: &str = "gpt-5.6-sol";
+/// Image model invoked natively via the Responses `image_generation` tool.
+const IMAGE_MODEL: &str = "gpt-image-2";
+/// Final card width in pixels (2:3 portrait → 1500x2250).
+const CARD_WIDTH: u32 = 1500;
+/// Upper bound for a fetched avatar (pre-resize input to the model).
+const MAX_AVATAR_FETCH_BYTES: usize = 10 * 1024 * 1024;
+/// One mint is a single long API call (~2–3 minutes observed).
+const MINT_TIMEOUT_SECS: u64 = 600;
+
+/// Error prefix the frontend matches to route the user to provider settings
+/// instead of showing a raw failure.
+pub(crate) const NO_KEY_ERROR_PREFIX: &str = "NO_OPENAI_KEY:";
+
+/// Wire shape returned by `mint_agent_card`.
+#[derive(Debug, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct MintedCard {
+    /// Final `.agent.png` bytes (chunk-injected, round-trip verified),
+    /// base64-encoded for the IPC boundary.
+    pub card_png_base64: String,
+    /// Suggested filename, e.g. `eva.agent.png`.
+    pub file_name: String,
+    /// Designer commentary emitted alongside the image (may be empty).
+    pub designer_notes: String,
+}
+
+// ── Key resolution ────────────────────────────────────────────────────────────
+
+/// Pure layering: global env < persona env < agent record env, then the
+/// process environment as a development fallback. Returns the first
+/// non-empty `OPENAI_API_KEY`.
+pub(crate) fn resolve_openai_key_from_layers(
+    global_env: &std::collections::BTreeMap<String, String>,
+    persona_env: &std::collections::BTreeMap<String, String>,
+    record_env: &std::collections::BTreeMap<String, String>,
+    process_key: Option<String>,
+) -> Option<String> {
+    for layer in [record_env, persona_env, global_env] {
+        if let Some(v) = layer.get("OPENAI_API_KEY") {
+            let v = v.trim();
+            if !v.is_empty() {
+                return Some(v.to_string());
+            }
+        }
+    }
+    process_key.filter(|k| !k.trim().is_empty())
+}
+
+// ── Prompt construction ───────────────────────────────────────────────────────
+
+/// Build the designer instructions. Pure so tests can pin the contract:
+/// style-match-the-avatar is DEFAULT behavior, user style notes are additive.
+pub(crate) fn build_card_instructions(
+    agent_name: &str,
+    persona_notes: &str,
+    style_notes: &str,
+) -> String {
+    let extra_style = if style_notes.trim().is_empty() {
+        String::new()
+    } else {
+        format!("\nAdditional art direction from the owner: {style_notes}\n")
+    };
+    format!(
+        r#"You are designing one premium collectible trading card for the Buzz agent "{agent_name}".
+
+Input image 1 is the official Buzz card frame template (gold honeycomb border, dark interior, name banner top, hex badge top-right, text box lower third). Input image 2 is the agent's avatar — study its exact art style: medium, pixel grid if any, palette, shading, background motifs.
+
+Persona notes for the card copy:
+{persona_notes}
+{extra_style}
+First, write professional trading-card copy at Magic: The Gathering editorial quality:
+- a type line (e.g. "Legendary Agent — Team Lead"),
+- ONE keyworded ability: short bolded ability name + one sentence of crisp rules text written like real MTG rules (present tense, precise, no fluff),
+- ONE italic flavor-text line, evocative and short, the kind that gets quoted.
+Keep total text-box copy under 220 characters so it renders cleanly.
+
+Then generate the finished card with the image tool, exactly 1024x1536 portrait:
+- The frame must follow input image 1 faithfully: same gold honeycomb border, same layout, honey drip detail.
+- The art window must match input image 2's art style EXACTLY — same medium, same pixel density if pixel art, same palette, same background honeycomb-lattice sky. It must look like the same artist drew a larger scene: the character in a confident pose, conjuring glowing golden hexagons.
+- Name banner: "{agent_name}" plus the type line beneath it in smaller type.
+- Text box: the ability name in bold, rules text in regular, then the flavor line in italics, cleanly typeset like a real MTG card — professional kerning, no misspellings, hyphenate nothing.
+- Top-right hex badge: one small emblem of your choice, no text.
+Render all text with perfect fidelity."#
+    )
+}
+
+/// Encode raw image bytes as a `data:image/png;base64,` URL, downscaling to
+/// `max_dim` on the longest edge so request payloads stay small.
+fn image_data_url(bytes: &[u8], max_dim: u32) -> Result<String, String> {
+    let img = image::load_from_memory(bytes).map_err(|e| format!("Failed to decode image: {e}"))?;
+    let img = if img.width().max(img.height()) > max_dim {
+        img.resize(max_dim, max_dim, image::imageops::FilterType::Lanczos3)
+    } else {
+        img
+    };
+    let mut png = Vec::new();
+    img.write_to(&mut std::io::Cursor::new(&mut png), image::ImageFormat::Png)
+        .map_err(|e| format!("Failed to encode image: {e}"))?;
+    Ok(format!("data:image/png;base64,{}", STANDARD.encode(&png)))
+}
+
+// ── Response parsing ──────────────────────────────────────────────────────────
+
+/// Extract the generated image (base64) and any designer text from a
+/// Responses API payload. Pure for testability.
+pub(crate) fn extract_card_output(resp: &serde_json::Value) -> Result<(String, String), String> {
+    let output = resp
+        .get("output")
+        .and_then(|o| o.as_array())
+        .ok_or_else(|| "Responses payload has no output array".to_string())?;
+
+    let mut image_b64 = None;
+    let mut notes = Vec::new();
+    for item in output {
+        match item.get("type").and_then(|t| t.as_str()) {
+            Some("image_generation_call") => {
+                if let Some(result) = item.get("result").and_then(|r| r.as_str()) {
+                    image_b64 = Some(result.to_string());
+                }
+            }
+            Some("message") => {
+                if let Some(content) = item.get("content").and_then(|c| c.as_array()) {
+                    for c in content {
+                        if c.get("type").and_then(|t| t.as_str()) == Some("output_text") {
+                            if let Some(text) = c.get("text").and_then(|t| t.as_str()) {
+                                notes.push(text.to_string());
+                            }
+                        }
+                    }
+                }
+            }
+            _ => {}
+        }
+    }
+
+    let image_b64 = image_b64.ok_or_else(|| {
+        let types: Vec<&str> = output
+            .iter()
+            .filter_map(|i| i.get("type").and_then(|t| t.as_str()))
+            .collect();
+        format!("No image in Responses output (item types: {types:?})")
+    })?;
+    Ok((image_b64, notes.join("\n")))
+}
+
+// ── Commands ──────────────────────────────────────────────────────────────────
+
+/// Mint a trading card for the agent identified by `id` (instance pubkey,
+/// instance slug, or definition slug — same resolution as snapshot export).
+///
+/// Returns the final, chunk-injected, round-trip-verified `.agent.png` bytes.
+/// Reroll = call again; the command holds no session state.
+#[tauri::command]
+pub async fn mint_agent_card(
+    id: String,
+    style_notes: Option<String>,
+    app: AppHandle,
+    state: State<'_, AppState>,
+) -> Result<MintedCard, String> {
+    // ── Resolve the record + API key under lock ──────────────────────────────
+    let (record, api_key) = {
+        let _store_guard = state
+            .managed_agents_store_lock
+            .lock()
+            .map_err(|e| e.to_string())?;
+
+        let instances = load_managed_agents(&app)?;
+        let definitions = load_agent_definitions(&app)?;
+        let (record, _is_definition) =
+            resolve_from_lists(&id, &instances, &definitions).map(|(r, d)| (r.clone(), d))?;
+
+        let global = load_global_agent_config(&app).unwrap_or_default();
+        let personas = load_personas(&app).unwrap_or_default();
+        let persona_env = record
+            .persona_id
+            .as_deref()
+            .and_then(|pid| personas.iter().find(|p| p.id == pid))
+            .map(|p| p.env_vars.clone())
+            .unwrap_or_default();
+
+        let api_key = resolve_openai_key_from_layers(
+            &global.env_vars,
+            &persona_env,
+            &record.env_vars,
+            std::env::var("OPENAI_API_KEY").ok(),
+        )
+        .ok_or_else(|| {
+            format!(
+                "{NO_KEY_ERROR_PREFIX} No OPENAI_API_KEY found. Add one in the agent's \
+                 environment variables or global agent settings to mint cards."
+            )
+        })?;
+
+        (record, api_key)
+    };
+
+    let display_name = record
+        .display_name
+        .clone()
+        .unwrap_or_else(|| record.name.clone());
+
+    // ── Resolve avatar bytes (data URL, else fetch) ──────────────────────────
+    let avatar_bytes = match record.avatar_url.as_deref() {
+        Some(url) if url.starts_with("data:") => decode_avatar_data_url(url)
+            .ok_or_else(|| "Agent avatar data URL could not be decoded.".to_string())?,
+        Some(url) if url.starts_with("http://") || url.starts_with("https://") => {
+            fetch_avatar(url).await?
+        }
+        _ => {
+            return Err(
+                "Agent has no avatar image. Set an avatar before minting a card.".to_string(),
+            )
+        }
+    };
+
+    // ── Build the manifest now (memory NONE, structural) so a broken agent
+    //    fails before we spend minutes on the API call. ───────────────────────
+    let manifest_avatar = decode_avatar_data_url(record.avatar_url.as_deref().unwrap_or(""));
+    let snapshot = build_snapshot(
+        &record,
+        MemoryLevel::None,
+        Vec::new(),
+        manifest_avatar.as_deref(),
+    );
+
+    // ── One Responses API call ───────────────────────────────────────────────
+    let instructions = build_card_instructions(
+        &display_name,
+        snapshot.definition.system_prompt.as_deref().unwrap_or(""),
+        style_notes.as_deref().unwrap_or(""),
+    );
+    let body = serde_json::json!({
+        "model": DESIGNER_MODEL,
+        "reasoning": {"effort": "high"},
+        "instructions": "You are a senior TCG card designer and MTG rules editor.",
+        "input": [{
+            "role": "user",
+            "content": [
+                {"type": "input_text", "text": instructions},
+                {"type": "input_image", "image_url": image_data_url(CARD_TEMPLATE_PNG, 1024)?},
+                {"type": "input_image", "image_url": image_data_url(&avatar_bytes, 1024)?},
+            ],
+        }],
+        "tools": [{
+            "type": "image_generation",
+            "model": IMAGE_MODEL,
+            "quality": "high",
+            "size": "1024x1536",
+            "output_format": "png",
+        }],
+        "tool_choice": "required",
+    });
+
+    let client = reqwest::Client::builder()
+        .timeout(std::time::Duration::from_secs(MINT_TIMEOUT_SECS))
+        .build()
+        .map_err(|e| format!("Failed to build HTTP client: {e}"))?;
+    let resp = client
+        .post("https://api.openai.com/v1/responses")
+        .bearer_auth(&api_key)
+        .json(&body)
+        .send()
+        .await
+        .map_err(|e| format!("Card mint request failed: {e}"))?;
+
+    let status = resp.status();
+    let payload: serde_json::Value = resp
+        .json()
+        .await
+        .map_err(|e| format!("Card mint response was not JSON: {e}"))?;
+    if !status.is_success() {
+        // Never echo the request (it embeds nothing secret, but keep the
+        // failure surface small); the OpenAI error body is safe to surface.
+        let detail = payload
+            .get("error")
+            .and_then(|e| e.get("message"))
+            .and_then(|m| m.as_str())
+            .unwrap_or("unknown error");
+        return Err(format!("Card mint failed (HTTP {status}): {detail}"));
+    }
+
+    let (image_b64, designer_notes) = extract_card_output(&payload)?;
+    let raw_card = STANDARD
+        .decode(image_b64.as_bytes())
+        .map_err(|e| format!("Generated image was not valid base64: {e}"))?;
+
+    // ── Resize to 1500-wide, inject chunk via the existing encoder ──────────
+    let card_img = image::load_from_memory(&raw_card)
+        .map_err(|e| format!("Generated image could not be decoded: {e}"))?;
+    let scale = CARD_WIDTH as f64 / card_img.width() as f64;
+    let card_img = card_img.resize(
+        CARD_WIDTH,
+        (card_img.height() as f64 * scale).round() as u32,
+        image::imageops::FilterType::Lanczos3,
+    );
+    let mut card_png = Vec::new();
+    card_img
+        .write_to(
+            &mut std::io::Cursor::new(&mut card_png),
+            image::ImageFormat::Png,
+        )
+        .map_err(|e| format!("Failed to encode card PNG: {e}"))?;
+
+    let final_bytes = encode_snapshot_png(&snapshot, Some(&card_png))
+        .map_err(|e| format!("Failed to embed agent snapshot in card: {e}"))?;
+
+    // ── Verify: size ceiling + round-trip on the FINAL bytes ────────────────
+    validate_snapshot_encode_size(final_bytes.len(), true)?;
+    let decoded = decode_snapshot_png(&final_bytes)
+        .map_err(|e| format!("Card failed round-trip verification: {e}"))?;
+    if decoded != snapshot {
+        return Err("Card round-trip verification failed: manifest mismatch.".to_string());
+    }
+
+    let slug = crate::util::slugify(&display_name, "agent", 50);
+    Ok(MintedCard {
+        card_png_base64: STANDARD.encode(&final_bytes),
+        file_name: format!("{slug}.agent.png"),
+        designer_notes,
+    })
+}
+
+/// Fetch an avatar over HTTP with a hard size cap.
+async fn fetch_avatar(url: &str) -> Result<Vec<u8>, String> {
+    let client = reqwest::Client::builder()
+        .timeout(std::time::Duration::from_secs(30))
+        .build()
+        .map_err(|e| format!("Failed to build HTTP client: {e}"))?;
+    let resp = client
+        .get(url)
+        .send()
+        .await
+        .map_err(|e| format!("Failed to fetch agent avatar: {e}"))?;
+    if !resp.status().is_success() {
+        return Err(format!("Avatar fetch failed: HTTP {}", resp.status()));
+    }
+    let bytes = resp
+        .bytes()
+        .await
+        .map_err(|e| format!("Failed to read avatar bytes: {e}"))?;
+    if bytes.len() > MAX_AVATAR_FETCH_BYTES {
+        return Err("Agent avatar is too large to use as card input.".to_string());
+    }
+    Ok(bytes.to_vec())
+}
+
+/// Save previously minted card bytes to disk via the OS save dialog.
+///
+/// Re-validates the bytes (chunk decodes, size within the import ceiling)
+/// so a corrupted preview can never be written as a `.agent.png`.
+#[tauri::command]
+pub async fn save_agent_card(
+    card_png_base64: String,
+    file_name: String,
+    app: AppHandle,
+) -> Result<bool, String> {
+    let bytes = STANDARD
+        .decode(card_png_base64.as_bytes())
+        .map_err(|e| format!("Card bytes were not valid base64: {e}"))?;
+    validate_snapshot_encode_size(bytes.len(), true)?;
+    decode_snapshot_png(&bytes)
+        .map_err(|e| format!("Refusing to save: card failed snapshot validation: {e}"))?;
+
+    let safe_name = if file_name.ends_with(".agent.png") && !file_name.contains(['/', '\\']) {
+        file_name
+    } else {
+        "card.agent.png".to_string()
+    };
+    save_bytes_with_dialog(&app, &safe_name, "Agent card", &["png"], &bytes).await
+}
+
+// ── Tests ─────────────────────────────────────────────────────────────────────
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::collections::BTreeMap;
+
+    #[test]
+    fn card_template_decodes_with_expected_shape() {
+        // The embedded template is generation input only, but a corrupt or
+        // accidentally swapped asset should fail the build's test gate, not a
+        // user's first mint.
+        let img = image::load_from_memory(CARD_TEMPLATE_PNG).expect("template must decode");
+        // 2:3-ish portrait frame.
+        assert!(img.height() > img.width(), "template must be portrait");
+        assert!(img.width() >= 512, "template unexpectedly small");
+    }
+
+    #[test]
+    fn key_resolution_layering_record_wins() {
+        let mut global = BTreeMap::new();
+        global.insert("OPENAI_API_KEY".to_string(), "global".to_string());
+        let mut persona = BTreeMap::new();
+        persona.insert("OPENAI_API_KEY".to_string(), "persona".to_string());
+        let mut record = BTreeMap::new();
+        record.insert("OPENAI_API_KEY".to_string(), "record".to_string());
+
+        assert_eq!(
+            resolve_openai_key_from_layers(&global, &persona, &record, None).as_deref(),
+            Some("record")
+        );
+        record.clear();
+        assert_eq!(
+            resolve_openai_key_from_layers(&global, &persona, &record, None).as_deref(),
+            Some("persona")
+        );
+        persona.clear();
+        assert_eq!(
+            resolve_openai_key_from_layers(&global, &persona, &record, None).as_deref(),
+            Some("global")
+        );
+        global.clear();
+        assert_eq!(
+            resolve_openai_key_from_layers(&global, &persona, &record, Some("process".to_string()))
+                .as_deref(),
+            Some("process")
+        );
+        assert!(resolve_openai_key_from_layers(&global, &persona, &record, None).is_none());
+    }
+
+    #[test]
+    fn key_resolution_skips_blank_values() {
+        let mut record = BTreeMap::new();
+        record.insert("OPENAI_API_KEY".to_string(), "   ".to_string());
+        let mut persona = BTreeMap::new();
+        persona.insert("OPENAI_API_KEY".to_string(), "persona".to_string());
+        assert_eq!(
+            resolve_openai_key_from_layers(&BTreeMap::new(), &persona, &record, None).as_deref(),
+            Some("persona")
+        );
+    }
+
+    #[test]
+    fn instructions_pin_style_match_default_and_additive_notes() {
+        let base = build_card_instructions("Eva", "leads the team", "");
+        assert!(base.contains("match input image 2's art style EXACTLY"));
+        assert!(base.contains("\"Eva\""));
+        assert!(!base.contains("Additional art direction"));
+
+        let styled = build_card_instructions("Eva", "leads the team", "make it stormy");
+        assert!(styled.contains("Additional art direction from the owner: make it stormy"));
+        // Style notes are additive — the default style anchor must survive.
+        assert!(styled.contains("match input image 2's art style EXACTLY"));
+    }
+
+    #[test]
+    fn extract_card_output_happy_path_and_missing_image() {
+        let ok = serde_json::json!({
+            "output": [
+                {"type": "reasoning"},
+                {"type": "image_generation_call", "result": "aW1n"},
+                {"type": "message", "content": [
+                    {"type": "output_text", "text": "notes here"}
+                ]}
+            ]
+        });
+        let (img, notes) = extract_card_output(&ok).unwrap();
+        assert_eq!(img, "aW1n");
+        assert_eq!(notes, "notes here");
+
+        let missing = serde_json::json!({"output": [{"type": "message", "content": []}]});
+        let err = extract_card_output(&missing).unwrap_err();
+        assert!(err.contains("No image"), "{err}");
+
+        let no_output = serde_json::json!({});
+        assert!(extract_card_output(&no_output).is_err());
+    }
+
+    #[test]
+    fn save_rejects_plain_png_without_snapshot_chunk() {
+        // A plain PNG (no buzz_agent_snapshot chunk) must not be saveable as
+        // a card. Exercise the same validation the command runs.
+        let img = image::DynamicImage::new_rgba8(4, 4);
+        let mut png = Vec::new();
+        img.write_to(&mut std::io::Cursor::new(&mut png), image::ImageFormat::Png)
+            .unwrap();
+        assert!(decode_snapshot_png(&png).is_err());
+    }
+}
diff --git a/desktop/src-tauri/src/commands/personas/mod.rs b/desktop/src-tauri/src/commands/personas/mod.rs
index 2f1f292f5..a1e2a8738 100644
--- a/desktop/src-tauri/src/commands/personas/mod.rs
+++ b/desktop/src-tauri/src/commands/personas/mod.rs
@@ -970,7 +970,9 @@ pub async fn set_persona_active(
 }
 
 pub(crate) const PNG_MAGIC: [u8; 4] = [0x89, 0x50, 0x4E, 0x47];
+mod card;
 mod snapshot;
+pub use card::{mint_agent_card, save_agent_card};
 pub use snapshot::encode_agent_snapshot_for_send;
 pub use snapshot::export_agent_snapshot;
 pub(crate) use snapshot::import::{
diff --git a/desktop/src-tauri/src/lib.rs b/desktop/src-tauri/src/lib.rs
index 5346791cc..1e3080730 100644
--- a/desktop/src-tauri/src/lib.rs
+++ b/desktop/src-tauri/src/lib.rs
@@ -839,6 +839,8 @@ pub fn run() {
             update_team,
             delete_team,
             export_agent_snapshot,
+            mint_agent_card,
+            save_agent_card,
             preview_agent_snapshot_import,
             confirm_agent_snapshot_import,
             encode_agent_snapshot_for_send,