---
title: "Get protocol configuration for a specific epoch"
method: GET
path: "/protocol-configuration/{epoch}"
---

# Get protocol configuration for a specific epoch

`GET /protocol-configuration/{epoch}`

Returns the information related to the protocol configuration at a given epoch:
  * epoch
  * protocol parameters
  * cardano transactions signing configuration
  * enabled signed entity types

## Path parameters

- `epoch` integer, required

## Response `200`

protocol configuration found

- ProtocolConfigurationMessage — Protocol configuration
  - `protocol_parameters` ProtocolParameters, required — Protocol cryptographic parameters
    - `k` integer, required — Quorum parameter
    - `m` integer, required — Security parameter (number of lotteries)
    - `phi_f` number, double, required — f in phi(w) = 1 - (1 - f)^w, where w is the stake of a participant
  - `cardano_transactions_signing_config` CardanoTransactionsSigningConfig — Cardano transactions signing configuration
    - `security_parameter` integer, required — Number of blocks to discard from the tip of the chain when importing Cardano transactions
    - `step` integer, required — Number of blocks between signature of Cardano transactions
  - `cardano_blocks_transactions_signing_config` CardanoBlocksTransactionsSigningConfig — Cardano blocks and transactions signing configuration
    - `security_parameter` integer, required — Number of blocks to discard from the tip of the chain when importing Cardano blocks and transactions
    - `step` integer, required — Number of blocks between signature of Cardano blocks and transactions
  - `available_signed_entity_types` SignedEntityTypes[], required — Available signed entity types that are signed by the aggregator

## Other responses

- `404` — protocol configuration not found
- `default` — protocol configuration error

## Changes

- **2026-05-20** `8ba930cf36c9` — 1 info
  - removed the `CardanoImmutableFilesFull` enum value from the `available_signed_entity_types/items/` response property for the response status `200`
- **2026-02-09** `7cb313f12e5f` — 1 warning, 1 info
  - added the new `CardanoBlocksTransactions` enum value to the `available_signed_entity_types/items/` response property for the response status `200`
  - added the optional property `cardano_blocks_transactions_signing_config` to the response with the `200` status
- **2025-11-20** `3ebfe437f6c8` — 1 breaking
  - the response property `cardano_transactions_signing_config` became optional for the status `200`
- **2025-10-17** `d18a103d55e2` — 1 warning
  - added the new `CardanoDatabase` enum value to the `available_signed_entity_types/items/` response property for the response status `200`
- **2025-10-16** `002ea1c8a54f` — 1 info
  - added the non-success response with the status `404`

[Full history](https://skmtc.dev/input-output-hk/apis/mithril-aggregator-server/changes/protocol-configuration/:epoch/get.md)

---

[API](https://skmtc.dev/input-output-hk/apis/mithril-aggregator-server.md) · [All operations](https://skmtc.dev/input-output-hk/apis/mithril-aggregator-server/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/input-output-hk/mithril-aggregator-server/revisions/bbad910c52a3/schema)