# Tezos-facts: machine-readable Tezos data, including a Prometheus service-discovery feed of public RPC nodes

**URL:** https://forum.tezosagora.org/t/tezos-facts-machine-readable-tezos-data-including-a-prometheus-service-discovery-feed-of-public-rpc-nodes/7145
**Category:** Project Updates
**Tags:** infrastructure
**Created:** [August 2, 2026, 12:07pm UTC](https://forum.tezosagora.org/t/tezos-facts-machine-readable-tezos-data-including-a-prometheus-service-discovery-feed-of-public-rpc-nodes/7145 "2026-08-02T12:07:30Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![cmehat](https://forum.tezosagora.org/user_avatar/forum.tezosagora.org/cmehat/32/2712_2.png) [@cmehat](https://forum.tezosagora.org/u/cmehat)
#### Post date: [August 2, 2026, 12:07pm UTC](https://forum.tezosagora.org/t/tezos-facts-machine-readable-tezos-data-including-a-prometheus-service-discovery-feed-of-public-rpc-nodes/7145/1 "2026-08-02T12:07:31Z")

</div>

Hi everyone,

I’d like to share **tezos-facts** , a small project that aggregates public information about Tezos public nodes into machine-readable JSON files, published for anyone to consume:

- **Published files:** [https://tezos-infra.gitlab.io/vigies/tezos-facts](https://tezos-infra.gitlab.io/vigies/tezos-facts)

### What it publishes

Every file is regenerated automatically from public sources:

- **`merged_prometheus_sd.json`** — all known public Tezos RPC nodes, aggregated and deduplicated from [teztnets.com](https://teztnets.com/teztnets.json), [taquito.io](https://taquito.io/rpc_nodes.json), [docs.tezos.com](https://docs.tezos.com/architecture/nodes) and octez.js, formatted as Prometheus HTTP service discovery. Targets carry labels like `tezos_network`, `provider`, and `source_sd`, so you can filter to just the networks or sources you care about.

Per-source SD files are also published if you’d rather consume a single source.

### Using it with Prometheus

The main use case is chain health monitoring: watching the head level of public nodes to detect head drift or a stalled chain. `merged_prometheus_sd.json` plugs directly into `http_sd_configs`, and since Tezos nodes expose JSON RPC (not Prometheus metrics), you pair it with the [Prometheus JSON exporter](https://github.com/prometheus-community/json_exporter):

```auto
scrape_configs:
  - job_name: tezos_public_rpc_head
    metrics_path: /probe
    params:
      module: [tezos_head_header]
    http_sd_configs:
      - url: https://tezos-infra.gitlab.io/vigies/tezos-facts/merged_prometheus_sd.json
        refresh_interval: 1h
    relabel_configs:
      # SD target host -> the RPC URL the JSON exporter must fetch
      - source_labels: [__address__]
        target_label: __param_target
        replacement: https://${1}/chains/main/blocks/head/header
      - source_labels: [__address__]
        target_label: instance
      # send the scrape to the JSON exporter instead of the node
      - target_label: __address__
        replacement: json-exporter:7979

```

And the JSON exporter module (`--config.file`):

```auto
modules:
  tezos_head_header:
    metrics:
      - name: tezos_public_node_head_level
        help: "Head block level from /chains/main/blocks/head/header"
        path: '{ .level }'

```

From there, a simple `max(tezos_public_node_head_level) by (tezos_network)` gives you the public head of each network — useful as a reference point to alert when your own nodes drift behind, or when a chain halts entirely. This is exactly how we use it in production to monitor our node fleet.

If you run a public RPC endpoint that isn’t listed in the upstream sources, the best way to appear in the feed is to get listed there (teztnets, taquito, or [docs.tezos.com](http://docs.tezos.com)).

* * *

Thanks @jevonearth for the json format on taquito 😉