Hiro Microblocks API

Read-only endpoints to obtain microblocks details

Work with this as data

Every API here is available over the APIs.io API and to AI agents over MCP.

MCP server

One button, every client — Claude, Cursor, VS Code and the rest.

https://apis.io/mcp

Tools for apis

7 MCP tools reach this
  • find_apisBrowse and filter every API in the catalog.
  • get_api_artifactsOne API's artifacts, grouped by type.
  • get_openapiThe primary OpenAPI for this API.
  • find_similar_apisAPIs that look like this one.
  • apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
  • resolveTurn a domain, URL or GitHub org into the provider it belongs to.
  • find_cohortsEvery scored population of providers in the catalog.
All 92 tools

Call it yourself

curl for this page
This API
curl "https://apis.io/api/v1/apis/hiro-microblocks-api"
All apis
curl "https://apis.io/api/v1/apis?limit=25"

Discovery needs no key. Ratings and market analysis are Pro.

Get an API key

Free tier, no email required.

A second provider on the same verified email joins the account you already have.

OpenAPI Specification

hiro-microblocks-api-openapi.yml Raw ↑
openapi: 3.0.3
info:
  title: Signer Metrics Accounts Microblocks API
  description: Welcome to the API reference overview for the Signer Metrics API.
  version: 1.0.3
servers:
- url: https://api.hiro.so/
  description: mainnet
- url: https://api.testnet.hiro.so/
  description: testnet
tags:
- name: Microblocks
  description: Read-only endpoints to obtain microblocks details
  externalDocs:
    description: Stacks Documentation - Microblocks
    url: https://docs.stacks.co/understand-stacks/microblocks
paths:
  /extended/v1/microblock/:
    get:
      operationId: get_microblock_list
      summary: Get recent microblocks
      tags:
      - Microblocks
      description: "Retrieves a list of microblocks.\n\n          If you need to actively monitor new microblocks, we highly recommend subscribing to [WebSockets or Socket.io](https://github.com/hirosystems/stacks-blockchain-api/tree/master/client) for real-time updates."
      parameters:
      - schema:
          minimum: 0
          default: 20
          maximum: 200
          title: Limit
          type: integer
        in: query
        name: limit
        required: false
        description: Max number of microblocks to fetch
      - schema:
          minimum: 0
          default: 0
          title: Offset
          type: integer
        in: query
        name: offset
        required: false
        description: Result offset
      responses:
        '200':
          description: GET request that returns microblocks
          content:
            application/json:
              schema:
                title: MicroblockListResponse
                description: GET request that returns microblocks
                type: object
                properties:
                  limit:
                    type: integer
                    example: 20
                  offset:
                    type: integer
                    example: 0
                  total:
                    type: integer
                    example: 1
                  results:
                    type: array
                    items:
                      title: Microblock
                      description: A microblock
                      type: object
                      properties:
                        canonical:
                          description: Set to `true` if the microblock corresponds to the canonical chain tip.
                          type: boolean
                        microblock_canonical:
                          description: Set to `true` if the microblock was not orphaned in a following anchor block. Defaults to `true` if the following anchor block has not yet been created.
                          type: boolean
                        microblock_hash:
                          description: The SHA512/256 hash of this microblock.
                          type: string
                        microblock_sequence:
                          description: A hint to describe how to order a set of microblocks. Starts at 0.
                          type: integer
                        microblock_parent_hash:
                          description: The SHA512/256 hash of the previous signed microblock in this stream.
                          type: string
                        block_height:
                          description: The anchor block height that confirmed this microblock.
                          type: integer
                        parent_block_height:
                          description: The height of the anchor block that preceded this microblock.
                          type: integer
                        parent_block_hash:
                          description: The hash of the anchor block that preceded this microblock.
                          type: string
                        parent_burn_block_hash:
                          description: The hash of the Bitcoin block that preceded this microblock.
                          type: string
                        parent_burn_block_time:
                          description: The block timestamp of the Bitcoin block that preceded this microblock.
                          type: integer
                        parent_burn_block_time_iso:
                          description: The ISO 8601 (YYYY-MM-DDTHH:mm:ss.sssZ) formatted block time of the bitcoin block that preceded this microblock.
                          type: string
                        parent_burn_block_height:
                          description: The height of the Bitcoin block that preceded this microblock.
                          type: integer
                        block_hash:
                          anyOf:
                          - description: The hash of the anchor block that confirmed this microblock. This wil be empty for unanchored microblocks
                            type: string
                          - type: 'null'
                        txs:
                          description: List of transactions included in the microblock
                          type: array
                          items:
                            type: string
                      required:
                      - canonical
                      - microblock_canonical
                      - microblock_hash
                      - microblock_sequence
                      - microblock_parent_hash
                      - block_height
                      - parent_block_height
                      - parent_block_hash
                      - parent_burn_block_hash
                      - parent_burn_block_time
                      - parent_burn_block_time_iso
                      - parent_burn_block_height
                      - block_hash
                      - txs
                required:
                - limit
                - offset
                - total
                - results
        4XX:
          description: Default Response
          content:
            application/json:
              schema:
                title: Error Response
                additionalProperties: true
                type: object
                properties:
                  error:
                    type: string
                  message:
                    type: string
                required:
                - error
  /extended/v1/microblock/{hash}:
    get:
      operationId: get_microblock_by_hash
      summary: Get microblock
      tags:
      - Microblocks
      description: Retrieves a specific microblock by `hash`
      parameters:
      - schema:
          type: string
        example: '0x3bfcdf84b3012adb544cf0f6df4835f93418c2269a3881885e27b3d58eb82d47'
        in: path
        name: hash
        required: true
        description: Hash of the microblock
      responses:
        '200':
          description: A microblock
          content:
            application/json:
              schema:
                title: Microblock
                description: A microblock
                type: object
                properties:
                  canonical:
                    description: Set to `true` if the microblock corresponds to the canonical chain tip.
                    type: boolean
                  microblock_canonical:
                    description: Set to `true` if the microblock was not orphaned in a following anchor block. Defaults to `true` if the following anchor block has not yet been created.
                    type: boolean
                  microblock_hash:
                    description: The SHA512/256 hash of this microblock.
                    type: string
                  microblock_sequence:
                    description: A hint to describe how to order a set of microblocks. Starts at 0.
                    type: integer
                  microblock_parent_hash:
                    description: The SHA512/256 hash of the previous signed microblock in this stream.
                    type: string
                  block_height:
                    description: The anchor block height that confirmed this microblock.
                    type: integer
                  parent_block_height:
                    description: The height of the anchor block that preceded this microblock.
                    type: integer
                  parent_block_hash:
                    description: The hash of the anchor block that preceded this microblock.
                    type: string
                  parent_burn_block_hash:
                    description: The hash of the Bitcoin block that preceded this microblock.
                    type: string
                  parent_burn_block_time:
                    description: The block timestamp of the Bitcoin block that preceded this microblock.
                    type: integer
                  parent_burn_block_time_iso:
                    description: The ISO 8601 (YYYY-MM-DDTHH:mm:ss.sssZ) formatted block time of the bitcoin block that preceded this microblock.
                    type: string
                  parent_burn_block_height:
                    description: The height of the Bitcoin block that preceded this microblock.
                    type: integer
                  block_hash:
                    anyOf:
                    - description: The hash of the anchor block that confirmed this microblock. This wil be empty for unanchored microblocks
                      type: string
                    - type: 'null'
                  txs:
                    description: List of transactions included in the microblock
                    type: array
                    items:
                      type: string
                required:
                - canonical
                - microblock_canonical
                - microblock_hash
                - microblock_sequence
                - microblock_parent_hash
                - block_height
                - parent_block_height
                - parent_block_hash
                - parent_burn_block_hash
                - parent_burn_block_time
                - parent_burn_block_time_iso
                - parent_burn_block_height
                - block_hash
                - txs
        4XX:
          description: Default Response
          content:
            application/json:
              schema:
                title: Error Response
                additionalProperties: true
                type: object
                properties:
                  error:
                    type: string
                  message:
                    type: string
                required:
                - error
  /extended/v1/microblock/unanchored/txs:
    get:
      operationId: get_unanchored_txs
      summary: Get the list of current transactions that belong to unanchored microblocks
      tags:
      - Microblocks
      description: Retrieves transactions that have been streamed in microblocks but not yet accepted or rejected in an anchor block
      responses:
        '200':
          description: Default Response
          content:
            application/json:
              schema:
                type: object
                properties:
                  total:
                    type: integer
                  results:
                    type: array
                    items:
                      anyOf:
                      - title: TokenTransferTransaction
                        type: object
                        properties:
                          tx_id:
                            description: Transaction ID
                            type: string
                          nonce:
                            description: Used for ordering the transactions originating from and paying from an account. The nonce ensures that a transaction is processed at most once. The nonce counts the number of times an account's owner(s) have authorized a transaction. The first transaction from an account will have a nonce value equal to 0, the second will have a nonce value equal to 1, and so on.
                            type: integer
                          fee_rate:
                            description: Transaction fee as Integer string (64-bit unsigned integer).
                            type: string
                          sender_address:
                            description: Address of the transaction initiator
                            type: string
                          sponsor_nonce:
                            type: integer
                          sponsored:
                            description: Denotes whether the originating account is the same as the paying account
                            type: boolean
                          sponsor_address:
                            type: string
                          post_condition_mode:
                            anyOf:
                            - type: string
                              enum:
                              - allow
                            - type: string
                              enum:
                              - deny
                          post_conditions:
                            type: array
                            items:
                              anyOf:
                              - type: object
                                properties:
                                  principal:
                                    anyOf:
                                    - type: object
                                      properties:
                                        type_id:
                                          type: string
                                          enum:
                                          - principal_origin
                                      required:
                                      - type_id
                                    - type: object
                                      properties:
                                        type_id:
                                          type: string
                                          enum:
                                          - principal_standard
                                        address:
                                          type: string
                                      required:
                                      - type_id
                                      - address
                                    - type: object
                                      properties:
                                        type_id:
                                          type: string
                                          enum:
                                          - principal_contract
                                        address:
                                          type: string
                                        contract_name:
                                          type: string
                                      required:
                                      - type_id
                                      - address
                                      - contract_name
                                  condition_code:
                                    anyOf:
                                    - type: string
                                      enum:
                                      - sent_equal_to
                                    - type: string
                                      enum:
                                      - sent_greater_than
                                    - type: string
                                      enum:
                                      - sent_greater_than_or_equal_to
                                    - type: string
                                      enum:
                                      - sent_less_than
                                    - type: string
                                      enum:
                                      - sent_less_than_or_equal_to
                                  amount:
                                    type: string
                                  type:
                                    type: string
                                    enum:
                                    - stx
                                required:
                                - principal
                                - condition_code
                                - amount
                                - type
                              - type: object
                                properties:
                                  principal:
                                    anyOf:
                                    - type: object
                                      properties:
                                        type_id:
                                          type: string
                                          enum:
                                          - principal_origin
                                      required:
                                      - type_id
                                    - type: object
                                      properties:
                                        type_id:
                                          type: string
                                          enum:
                                          - principal_standard
                                        address:
                                          type: string
                                      required:
                                      - type_id
                                      - address
                                    - type: object
                                      properties:
                                        type_id:
                                          type: string
                                          enum:
                                          - principal_contract
                                        address:
                                          type: string
                                        contract_name:
                                          type: string
                                      required:
                                      - type_id
                                      - address
                                      - contract_name
                                  condition_code:
                                    anyOf:
                                    - type: string
                                      enum:
                                      - sent_equal_to
                                    - type: string
                                      enum:
                                      - sent_greater_than
                                    - type: string
                                      enum:
                                      - sent_greater_than_or_equal_to
                                    - type: string
                                      enum:
                                      - sent_less_than
                                    - type: string
                                      enum:
                                      - sent_less_than_or_equal_to
                                  amount:
                                    type: string
                                  type:
                                    type: string
                                    enum:
                                    - fungible
                                  asset:
                                    type: object
                                    properties:
                                      asset_name:
                                        type: string
                                      contract_address:
                                        type: string
                                      contract_name:
                                        type: string
                                    required:
                                    - asset_name
                                    - contract_address
                                    - contract_name
                                required:
                                - principal
                                - condition_code
                                - amount
                                - type
                                - asset
                              - type: object
                                properties:
                                  principal:
                                    anyOf:
                                    - type: object
                                      properties:
                                        type_id:
                                          type: string
                                          enum:
                                          - principal_origin
                                      required:
                                      - type_id
                                    - type: object
                                      properties:
                                        type_id:
                                          type: string
                                          enum:
                                          - principal_standard
                                        address:
                                          type: string
                                      required:
                                      - type_id
                                      - address
                                    - type: object
                                      properties:
                                        type_id:
                                          type: string
                                          enum:
                                          - principal_contract
                                        address:
                                          type: string
                                        contract_name:
                                          type: string
                                      required:
                                      - type_id
                                      - address
                                      - contract_name
                                  condition_code:
                                    anyOf:
                                    - type: string
                                      enum:
                                      - sent
                                    - type: string
                                      enum:
                                      - not_sent
                                  type:
                                    type: string
                                    enum:
                                    - non_fungible
                                  asset_value:
                                    type: object
                                    properties:
                                      hex:
                                        type: string
                                      repr:
                                        type: string
                                    required:
                                    - hex
                                    - repr
                                  asset:
                                    type: object
                                    properties:
                                      asset_name:
                                        type: string
                                      contract_address:
                                        type: string
                                      contract_name:
                                        type: string
                                    required:
                                    - asset_name
                                    - contract_address
                                    - contract_name
                                required:
                                - principal
                                - condition_code
                                - type
                                - asset_value
                                - asset
                          anchor_mode:
                            description: '`on_chain_only`: the transaction MUST be included in an anchored block, `off_chain_only`: the transaction MUST be included in a microblock, `any`: the leader can choose where to include the transaction.'
                            anyOf:
                            - type: string
                              enum:
                              - on_chain_only
                            - type: string
                              enum:
                              - off_chain_only
                            - type: string
                              enum:
                              - any
                          block_hash:
                            description: Hash of the blocked this transactions was associated with
                            type: string
                          block_height:
                            description: Height of the block this transactions was associated with
                            type: integer
                          block_time:
                            description: Unix timestamp (in seconds) indicating when this block was mined.
                            type: number
                          block_time_iso:
                            description: An ISO 8601 (YYYY-MM-DDTHH:mm:ss.sssZ) indicating when this block was mined.
                            type: string
                          burn_block_time:
                            description: Unix timestamp (in seconds) indicating when this block was mined.
                            type: integer
                          burn_block_height:
                            description: Height of the anchor burn block.
                            type: integer
                          burn_block_time_iso:
                            description: An ISO 8601 (YYYY-MM-DDTHH:mm:ss.sssZ) timestamp indicating when this block was mined.
                            type: string
                          parent_burn_block_time:
                            description: Unix timestamp (in seconds) indicating when this parent block was mined
                            type: integer
                          parent_burn_block_time_iso:
                            description: An ISO 8601 (YYYY-MM-DDTHH:mm:ss.sssZ) timestamp indicating when this parent block was mined.
                            type: string
                          canonical:
                            description: Set to `true` if block corresponds to the canonical chain tip
                            type: boolean
                          tx_index:
                            description: Index of the transaction, indicating the order. Starts at `0` and increases with each transaction
                            type: integer
                          tx_status:
                            description: Status of the transaction
                            anyOf:
                            - type: string
                              enum:
                              - success
                            - type: string
                              enum:
                              - abort_by_response
                            - type: string
                              enum:
                              - abort_by_post_condition
                          tx_result:
                            description: Result of the transaction. For contract calls, this will show the value returned by the call. For other transaction types, this will return a boolean indicating the success of the transaction.
                            additionalProperties: false
                            type: object
                            properties:
                              hex:
                                description: Hex string representing the value fo the transaction result
                                type: string
                              repr:
                                description: Readable string of the transaction result
                                type: string
                            required:
                            - hex
                            - repr
                          event_count:
                            description: Number of transaction events
                            type: integer
                          parent_block_hash:
                            description: Hash of the previous block.
                            type: string
                          is_unanchored:
                            description: True if the transaction is included in a microblock that has not been confirmed by an anchor block.
                            type: boolean
                          microblock_hash:
                            description: The microblock hash that this transaction was streamed in. If the transaction was batched in an anchor block (not included within a microblock) then this value will be an empty string.
                            type: string
                          microblock_sequence:
                            description: The microblock sequence number that this transaction was streamed in. If the transaction was batched in an anchor block (not included within a microblock) then this value will be 2147483647 (0x7fffffff, the max int32 value), this value preserves logical transaction ordering on (block_height, microblock_sequence, tx_index).
                            type: integer
                          microblock_canonical:
                            description: Set to `true` if microblock is anchored in the canonical chain tip, `false` if the transaction was orphaned in a micro-fork.
                            type: boolean
                          execution_cost_read_count:
                            description: Execution cost read count.
                            type: integer
                          execution_cost_read_length:
                            description: Execution cost read length.
                            type: integer
                          execution_cost_runtime:
                            description: Execution cost runtime.
                            type: integer
                          execution_cost_write_count:
                            description: Execution cost write count.
                            type: integer
                          execution_cost_write_length:
                            description: Execution cost write length.
                            type: integer
                          vm_error:
                            anyOf:
                            - description: Clarity VM error produced by this transaction
                              type: string
                            - type: 'null'
                          events:
                            type: array
                            items:
                              anyOf:
                              - title: SmartContractLogTransactionEvent
                                description: Only present in `smart_contract` and `contract_call` tx types.
                                type: object
                                allOf:
                                - title: AbstractTransactionEvent
                                  type: object
                                  properties:
                                    event_index:
                                      type: integer
                                  required:
                                  - event_index
                                - type: object
                                  properties:
                                    event_type:
                                      type: string
                                      enum:
                                      - smart_contract_log
                                    tx_id:
                                      type: string
                                    contract_log:
                                      type: object
                                      properties:
                                        contract_id:
                                          type: string
                                        topic:
                                          type: string
                                        value:
                                          type: object
                                          properties:
           

# --- truncated at 32 KB (222 KB total) ---
# Full source: https://raw.githubusercontent.com/api-evangelist/hiro/refs/heads/main/openapi/hiro-microblocks-api-openapi.yml