# Download From Swanlab Url > Download per-step time-series metric data (reward, entropy, response length, etc.) from a SwanLab cloud run URL as a pandas.DataFrame. Use when the user provides a SwanLab URL and wants to fetch or analyze training curves. - Skill: `modelscope/download-from-swanlab-url` (Agent Skill) - Install (CLI): `npx skillmds@latest add modelscope/download-from-swanlab-url` - Raw SKILL.md: https://api.skillmd.com/api/skills/modelscope/download-from-swanlab-url/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: DevOps & Infra - Author: modelscope (https://skillmd.com/u/modelscope) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/modelscope/download-from-swanlab-url --- # Skill: Download metric data from a SwanLab run URL ## Goal Given a SwanLab cloud URL of the form ``` https://swanlab.cn/@//runs//chart ``` fetch the per-step time-series data for one or more metrics (e.g. reward, entropy, response length) as a `pandas.DataFrame` for downstream plotting or analysis. ## Trial-and-error log (read first; saves hours) The shortcuts you might try **do not work**: 1. **WebFetch / `curl` of the chart page** — the page is a Vue SPA. The HTML body is just `
`; no chart data is embedded. Don't bother scraping HTML. 2. **Direct REST probe (`curl https://api.swanlab.cn/api/v1/runs/`)** — returns `404 Not Found` even with a valid api key. The public REST surface is not the v1 path; use the Python SDK. 3. **`swanlab verify` says you're logged in** — but the env may point to a private cloud. On this host: ``` $ swanlab verify swanlab: You are logged into https://cloud-20.agent-matrix.com as fuqingxu ``` This is **not** swanlab.cn. The shell exports `SWANLAB_API_HOST` and `SWANLAB_WEB_HOST` in `~/.bashrc`, redirecting the SDK to a different deployment. Calling `OpenApi(api_key=...)` then fails with `Login failed: 404 Not Found` because `/login/api_key` only exists on swanlab.cn's API host. 4. **Metric keys are NOT what the UI shows.** The chart card titled "reward" is logged as `critic/rewards/mean`. Asking `get_metrics(keys=['reward'])` returns code 404. You **must** probe candidate keys (see the cheat sheet below). 5. **`get_summary` to enumerate keys** — does not work for non-cloned runs. When `rootExpId` / `rootProId` are `None` (i.e. the run was not cloned from another project), `experiment.get_summary` returns HTTP 400 "Bad Request". Skip it; probe candidate keys directly with `get_metrics`. ## The working recipe ### 1. Prerequisites - `swanlab` Python package (>= 0.7.4 confirmed). - An api key for `swanlab.cn`. On this machine it is stored in `~/.swanlab/.netrc`: ``` machine https://api.swanlab.cn login https://swanlab.cn password ``` Read the password field from there if you don't have it on hand. ### 2. Parse the URL ```python import re URL = "https://swanlab.cn/@binaryhusky/spy-game-rl/runs/zku3ujg2k3unvt61jbu0s/chart" m = re.match(r"https?://swanlab\.cn/@([^/]+)/([^/]+)/runs/([^/]+)", URL) username, project, exp_id = m.group(1), m.group(2), m.group(3) ``` ### 3. Override env vars BEFORE importing `swanlab` Critical: if your shell has `SWANLAB_API_HOST` / `SWANLAB_WEB_HOST` / `SWANLAB_API_KEY` pointing to a private cloud, the SDK silently uses them. Either run via `env -i` or unset them: ```bash unset SWANLAB_API_KEY SWANLAB_API_HOST SWANLAB_WEB_HOST SWANLAB_API_HOST=https://api.swanlab.cn/api \ SWANLAB_WEB_HOST=https://swanlab.cn \ python your_script.py ``` Note: `SWANLAB_API_HOST` for swanlab.cn ends with `/api` (the SDK default in `swanlab/env.py`); without that suffix login also returns 404. ### 4. Open the API and fetch metadata ```python import swanlab api = swanlab.OpenApi(api_key="") # raises ValidationError if hosts wrong exp = api.get_experiment(project=project, exp_id=exp_id, username=username) assert exp.code == 200, exp.errmsg print(exp.data.name, exp.data.state) # exp.data.profile['config'] contains the full training config (verl-style nested dict) ``` ### 5. Discover the right metric keys The keys you ask for must match what was logged. For a verl-based AgentJet run, the working names are: | You might think | Actual logged key | | --------------- | ----------------------- | | `reward` | `critic/rewards/mean` | | `entropy` | `actor/entropy` | | `response_length` | `response_length/mean` | | `pg_loss` | `actor/pg_loss` | Other common ones: `response_length/max`, `response_length/min`, `critic/score/mean`. Probe defensively — `get_metrics` returns `code=200` and N rows on hit, `code=404, rows=0` on miss: ```python candidates = [ "critic/rewards/mean", "critic/score/mean", "actor/entropy", "actor/entropy_loss", "actor/pg_loss", "response_length/mean", "response_length/max", "response_length/min", ] for k in candidates: r = api.get_metrics(exp_id=exp_id, keys=k) print(f"{k:40s} code={r.code} rows={0 if r.data is None else len(r.data)}") ``` ### 6. Fetch and save ```python keys = ["critic/rewards/mean", "actor/entropy", "response_length/mean"] r = api.get_metrics(exp_id=exp_id, keys=keys) df = r.data # indexed by `step`; one column per key + one `_timestamp` column df.to_csv("metrics.csv") ``` The DataFrame layout is: ``` actor/entropy actor/entropy_timestamp critic/rewards/mean ... step 1 0.5569 1774003810000 0.7271 2 0.5732 1774004325000 0.7589 ... ``` The `_timestamp` columns are unix millis; usually you can drop them and plot against the `step` index. ## End-to-end runnable snippet ```python """Fetch reward/entropy/response_length curves from a swanlab.cn run URL.""" import os, re, sys # Strip any private-cloud overrides BEFORE importing swanlab. for v in ("SWANLAB_API_KEY", "SWANLAB_API_HOST", "SWANLAB_WEB_HOST"): os.environ.pop(v, None) os.environ["SWANLAB_API_HOST"] = "https://api.swanlab.cn/api" os.environ["SWANLAB_WEB_HOST"] = "https://swanlab.cn" import swanlab URL = sys.argv[1] API_KEY = sys.argv[2] # or read from ~/.swanlab/.netrc m = re.match(r"https?://swanlab\.cn/@([^/]+)/([^/]+)/runs/([^/]+)", URL) username, project, exp_id = m.groups() api = swanlab.OpenApi(api_key=API_KEY) keys = ["critic/rewards/mean", "actor/entropy", "response_length/mean"] r = api.get_metrics(exp_id=exp_id, keys=keys) assert r.code == 200, r.errmsg df = r.data.rename(columns={ "critic/rewards/mean": "reward", "actor/entropy": "entropy", "response_length/mean": "response_length", }) df.to_csv("metrics.csv") print(df.head()) ``` ## Plot recipe (seaborn, optional) ```python import seaborn as sns, matplotlib.pyplot as plt, pandas as pd df = pd.read_csv("metrics.csv").sort_values("step") sns.set_theme(context="paper", style="whitegrid") fig, axes = plt.subplots(1, 3, figsize=(11.5, 3.0)) palette = sns.color_palette("deep") for ax, (col, title, c) in zip(axes, [ ("reward", "Reward", palette[0]), ("entropy", "Policy Entropy", palette[3]), ("response_length", "Response Length", palette[2]), ]): sns.lineplot(data=df, x="step", y=col, ax=ax, color=c, linewidth=1.6) ax.set_title(title); ax.set_xlabel("Training step"); ax.set_ylabel("") fig.tight_layout() fig.savefig("curves.pdf", bbox_inches="tight") ``` ## Troubleshooting cheat sheet | Symptom | Likely cause | Fix | | --- | --- | --- | | `ValidationError: Login failed: 404 Not Found` on `OpenApi(api_key=...)` | `SWANLAB_API_HOST` points to a private cloud, or missing `/api` suffix | Unset the env vars and explicitly set `SWANLAB_API_HOST=https://api.swanlab.cn/api` | | `get_metrics` returns `code=404, "No data found"` | Wrong key name (UI label != log key) | Probe with the cheat sheet in §5; remember verl prefixes (`actor/`, `critic/`, `response_length/...`) | | `get_summary` returns `code=400, "Bad Request"` | Run is not a clone; `rootExpId`/`rootProId` are None | Don't use `get_summary` for non-cloned runs; just probe `get_metrics` | | `OpenApi.login_info` is not callable | It's a property, not a method | Access as `api.login_info` (no `()`) | | WebFetch returns "no data" / SPA shell | Chart page is Vue-rendered client-side | Use the SDK; do not scrape HTML | | `swanlab verify` shows wrong host | `~/.bashrc` exports redirect SDK to a private cloud | Override env at script start, before `import swanlab` |