generated: '2026-07-19'
method: searched
source: https://github.com/paritytech/substrate-api-sidecar/blob/master/CHANGELOG.md, openapi/kusama-sidecar-openapi.yaml,
  live RPC probe of https://kusama-rpc.polkadot.io/
versioning:
  chain:
    scheme: runtime spec_version (monotonic integer), bumped by on-chain runtime upgrade
    current_spec_name: kusama
    current_spec_version: 2003000
    current_impl_name: parity-kusama
    current_node_version: 1.24.0-660acefe665
    transaction_version: 26
    observed_at: '2026-07-19'
    source: state_getRuntimeVersion on https://kusama-rpc.polkadot.io/
    notes: >-
      A bump in transaction_version signals a breaking change to extrinsic encoding — offline signers and
      indexers must re-fetch metadata. spec_version bumps alone may be non-breaking. This is the closest
      thing Kusama has to an API version, and it changes by on-chain governance, not by a vendor release.
  json_rpc:
    scheme: method-name suffixed families (_v1, _unstable) per the Polkadot JSON-RPC interface spec
    spec: https://paritytech.github.io/json-rpc-interface-spec/
    stable_families:
    - chainHead_v1
    - archive_v1
    - transaction_v1
    - transactionWatch_v1
    - chainSpec_v1
    unstable_observed:
    - system_unstable_networkState
    legacy_families:
    - chain_*
    - state_*
    - author_*
    - system_*
    - payment_*
    - childstate_*
    notes: >-
      The legacy families remain served on kusama-rpc.polkadot.io (probed 2026-07-19) but the interface
      spec positions the _v1 families as the forward path for new clients, particularly light clients.
  rest_sidecar:
    scheme: semver on the substrate-api-sidecar release
    current_version: 20.14.1
    released: '2026-04-28'
deprecation:
  policy_published: true
  policy_url: https://github.com/paritytech/substrate-api-sidecar/blob/master/CHANGELOG.md
  rfc8594_sunset_headers: false
  notes: >-
    Deprecation is announced in-band — in the OpenAPI info.description, in the CHANGELOG, and inline in
    individual operation summaries — rather than via RFC 8594 Sunset/Deprecation response headers. No
    Sunset or Deprecation header was observed on live responses from the Kusama sidecar.
  deprecated_products:
  - name: substrate-api-sidecar
    status: deprecated
    announced: '2026-04-28'
    announced_in: v20.14.1 release notes and OpenAPI info.description
    superseded_by: polkadot-rest-api
    successor_repository: https://github.com/paritytech/polkadot-rest-api
    successor_docs: https://paritytech.github.io/polkadot-rest-api/
    successor_crate: https://crates.io/crates/polkadot-rest-api
    successor_docker: paritytech/polkadot-rest-api:v0.1.0
    migration_guide: https://github.com/paritytech/polkadot-rest-api/blob/main/docs/guides/MIGRATION.md
    compatibility: 1:1 API compatibility, endpoints served under /v1/ (e.g. /v1/blocks/head)
    support_commitment: 'Final feature release. Only critical-security fixes will be backported, if any.'
    sunset_date: null
  deprecated_operations:
    source: openapi/kusama-sidecar-openapi.yaml (summaries carrying "DEPRECATION NOTE")
    reason: Phased out in favor of Agile Coretime; the paras/auctions/crowdloans model is being replaced
      by coretime regions and renewals.
    replacement_tag: coretime
    paths:
    - GET /paras
    - GET /paras/auctions/current
    - GET /paras/crowdloans
    - GET /paras/head/backed-candidates
    - GET /paras/head/included-candidates
    - GET /paras/leases/current
    - GET /paras/{paraId}/crowdloan-info
    - GET /paras/{paraId}/lease-info
status_page:
  present: false
  notes: >-
    Neither kusama.network nor Parity publishes a hosted status page for the Kusama public RPC or sidecar
    endpoints (searched 2026-07-19). Liveness is instead observable directly from the chain interface.
  liveness_probes:
  - name: node health
    endpoint: POST https://kusama-rpc.polkadot.io/ {"method":"system_health"}
    observed: '{"peers":74,"isSyncing":false,"shouldHavePeers":true}'
    observed_at: '2026-07-19'
  - name: sidecar node version
    endpoint: GET https://kusama-public-sidecar.parity-chains.parity.io/node/version
    observed: '{"clientVersion":"1.24.0-660acefe665","clientImplName":"parity-kusama","chain":"Kusama"}'
    observed_at: '2026-07-19'
  - name: kusama asset hub sidecar
    endpoint: GET https://kusama-asset-hub-public-sidecar.parity-chains.parity.io/node/version
    observed: HTTP 500 "WebSocket is not connected"
    observed_at: '2026-07-19'
    note: Recorded as observed; the Asset Hub public sidecar was not serving at probe time.
sla:
  published: false
  notes: >-
    The public RPC and sidecar endpoints are best-effort community infrastructure with no published SLA.
    Production consumers are directed to run their own node or use a commercial RPC provider.
network_position:
  role: canary network
  relationship: Runs the same Polkadot SDK codebase as Polkadot; runtime upgrades, governance changes,
    and coretime/parachain mechanics ship to Kusama first and reach Polkadot after proving out.
  governance: OpenGov (on-chain referenda) — https://kusama.subsquare.io/ and https://kusama.polkassembly.io/
  implication: Breaking behavior changes reach Kusama earlier and faster than Polkadot by design.