BlockVectra: multi-chain RPC & Data API

Call JSON-RPC Method

rpc_call

Read-only

Execute a read-only JSON-RPC 2.0 method on a specified blockchain network using your BlockVectra API key, or via the keyless public endpoint if available on the chain. Chain slugs look like 'base_mainnet'; take them from list_chains. Without a key the call goes to the keyless endpoint /v1/{chain}/public (the chain's public.url in list_chains), which only serves the methods listed in that chain's public.methods. Write methods (such as 'eth_sendRawTransaction') are not supported in rpc_call; use 'send_raw_transaction' instead. Consult the Ethereum JSON-RPC specification (https://ethereum.org/en/developers/docs/apis/json-rpc/) and the BlockVectra method reference (https://docs.blockvectra.com/en/api/json-rpc/methods/). With a key, set the 'x-api-key' or 'Authorization: Bearer ' HTTP header in your MCP client configuration for full access (keys must not be passed in tool parameters or chat). Returns the raw JSON-RPC response from the server.

Input Schema

TableJSON Schema

Name	Required	Description
`chain`	Yes	Target blockchain network slug (e.g. 'base_mainnet'). Must exist in GET /v1/chains; list_chains returns the valid slugs.
`method`	Yes	JSON-RPC 2.0 method name (e.g. 'eth_blockNumber', 'eth_call', 'eth_getLogs'). Write methods are not accepted.
`params`	No	Optional JSON-RPC parameter array. Defaults to [].

Output Schema

TableJSON Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedOct 18, 2026

changedOutput schema / anyOf

Previous value: -[
-  {
-    "allOf": [
-      {
-        "properties": {
-          "balance_units": {
-            "description": "Remaining balance units after this request (only present when balance is known and x-bv-meter: 1 was sent).",
-            "type": "integer"
-          },
-          "cu_charged": {
-            "description": "Compute Units billed for this request (only present when charged and x-bv-meter: 1 was sent).",
-            "type": "integer"
-          },
-          "error": {
-            "properties": {
-              "code": {
-                "type": "number"
-              },
-              "docs_url": {
-                "type": [
-                  "string",
-                  "null"
-                ]
-              },
-              "message": {
-                "type": "string"
-              },
-              "reason": {
-                "type": [
-                  "string",
-                  "null"
-                ]
-              }
-            },
-            "type": [
-              "object",
-              "string"
-            ]
-          },
-          "help": {
-            "properties": {
-              "guide_url": {
-                "type": "string"
-              },
-              "tool": {
-                "type": "string"
-              }
-            },
-            "type": "object"
-          },
-          "id": {
-            "type": [
-              "number",
-              "string",
-              "null"
-            ]
-          },
-          "jsonrpc": {
-            "type": "string"
-          },
-          "message": {
-            "type": "string"
-          },
-          "result": {},
-          "signup_url": {
-            "description": "Registration and sign-up URL (returned when rate-limited on the public endpoint).",
-            "type": "string"
-          }
-        },
-        "type": "object"
-      },
-      {
-        "not": {
-          "properties": {
-            "error": {
-              "const": "invalid_tool_arguments",
-              "type": "string"
-            }
-          },
-          "required": [
-            "error"
-          ],
-          "type": "object"
-        }
-      }
-    ]
-  },
-  {
-    "additionalProperties": false,
-    "properties": {
-      "error": {
-        "const": "invalid_tool_arguments",
-        "type": "string"
-      },
-      "message": {
-        "minLength": 1,
-        "type": "string"
-      },
-      "reason": {
-        "enum": [
-          "invalid_root",
-          "schema_type",
-          "schema_enum",
-          "undeclared_property",
-          "credential_field",
-          "credential_value"
-        ],
-        "type": "string"
-      }
-    },
-    "required": [
-      "error",
-      "reason",
-      "message"
-    ],
-    "type": "object"
-  }
-]New value: +[
+  {
+    "allOf": [
+      {
+        "anyOf": [
+          {
+            "allOf": [
+              {
+                "properties": {
+                  "balance_units": {
+                    "description": "Remaining balance units after this request (only present when balance is known and x-bv-meter: 1 was sent).",
+                    "type": "integer"
+                  },
+                  "cu_charged": {
+                    "description": "Compute Units billed for this request (only present when charged and x-bv-meter: 1 was sent).",
+                    "type": "integer"
+                  },
+                  "error": {
+                    "properties": {
+                      "code": {
+                        "type": "number"
+                      },
+                      "docs_url": {
+                        "type": [
+                          "string",
+                          "null"
+                        ]
+                      },
+                      "message": {
+                        "type": "string"
+                      },
+                      "reason": {
+                        "type": [
+                          "string",
+                          "null"
+                        ]
+                      }
+                    },
+                    "type": [
+                      "object",
+                      "string"
+                    ]
+                  },
+                  "help": {
+                    "properties": {
+                      "guide_url": {
+                        "type": "string"
+                      },
+                      "tool": {
+                        "type": "string"
+                      }
+                    },
+                    "type": "object"
+                  },
+                  "id": {
+                    "type": [
+                      "number",
+                      "string",
+                      "null"
+                    ]
+                  },
+                  "jsonrpc": {
+                    "type": "string"
+                  },
+                  "message": {
+                    "type": "string"
+                  },
+                  "result": {},
+                  "signup_url": {
+                    "description": "Registration and sign-up URL (returned when rate-limited on the public endpoint).",
+                    "type": "string"
+                  }
+                },
+                "type": "object"
+              },
+              {
+                "not": {
+                  "properties": {
+                    "error": {
+                      "const": "executor_request_rejected",
+                      "type": "string"
+                    }
+                  },
+                  "required": [
+                    "error"
+                  ],
+                  "type": "object"
+                }
+              }
+            ]
+          },
+          {
+            "additionalProperties": false,
+            "properties": {
+              "error": {
+                "const": "executor_request_rejected",
+                "type": "string"
+              },
+              "message": {
+                "minLength": 1,
+                "type": "string"
+              },
+              "reason": {
+                "enum": [
+                  "chain_required",
+                  "method_required",
+                  "unknown_chain"
+                ],
+                "type": "string"
+              }
+            },
+            "required": [
+              "error",
+              "reason",
+              "message"
+            ],
+            "type": "object"
+          }
+        ],
+        "type": "object"
+      },
+      {
+        "not": {
+          "properties": {
+            "error": {
+              "const": "invalid_tool_arguments",
+              "type": "string"
+            }
+          },
+          "required": [
+            "error"
+          ],
+          "type": "object"
+        }
+      }
+    ]
+  },
+  {
+    "additionalProperties": false,
+    "properties": {
+      "error": {
+        "const": "invalid_tool_arguments",
+        "type": "string"
+      },
+      "message": {
+        "minLength": 1,
+        "type": "string"
+      },
+      "reason": {
+        "enum": [
+          "invalid_root",
+          "schema_type",
+          "schema_enum",
+          "undeclared_property",
+          "credential_field",
+          "credential_value"
+        ],
+        "type": "string"
+      }
+    },
+    "required": [
+      "error",
+      "reason",
+      "message"
+    ],
+    "type": "object"
+  }
+]

Changed2 schema fields changedOct 18, 2026

addedOutput schema / anyOf

Added value: +[
+  {
+    "allOf": [
+      {
+        "properties": {
+          "balance_units": {
+            "description": "Remaining balance units after this request (only present when balance is known and x-bv-meter: 1 was sent).",
+            "type": "integer"
+          },
+          "cu_charged": {
+            "description": "Compute Units billed for this request (only present when charged and x-bv-meter: 1 was sent).",
+            "type": "integer"
+          },
+          "error": {
+            "properties": {
+              "code": {
+                "type": "number"
+              },
+              "docs_url": {
+                "type": [
+                  "string",
+                  "null"
+                ]
+              },
+              "message": {
+                "type": "string"
+              },
+              "reason": {
+                "type": [
+                  "string",
+                  "null"
+                ]
+              }
+            },
+            "type": [
+              "object",
+              "string"
+            ]
+          },
+          "help": {
+            "properties": {
+              "guide_url": {
+                "type": "string"
+              },
+              "tool": {
+                "type": "string"
+              }
+            },
+            "type": "object"
+          },
+          "id": {
+            "type": [
+              "number",
+              "string",
+              "null"
+            ]
+          },
+          "jsonrpc": {
+            "type": "string"
+          },
+          "message": {
+            "type": "string"
+          },
+          "result": {},
+          "signup_url": {
+            "description": "Registration and sign-up URL (returned when rate-limited on the public endpoint).",
+            "type": "string"
+          }
+        },
+        "type": "object"
+      },
+      {
+        "not": {
+          "properties": {
+            "error": {
+              "const": "invalid_tool_arguments",
+              "type": "string"
+            }
+          },
+          "required": [
+            "error"
+          ],
+          "type": "object"
+        }
+      }
+    ]
+  },
+  {
+    "additionalProperties": false,
+    "properties": {
+      "error": {
+        "const": "invalid_tool_arguments",
+        "type": "string"
+      },
+      "message": {
+        "minLength": 1,
+        "type": "string"
+      },
+      "reason": {
+        "enum": [
+          "invalid_root",
+          "schema_type",
+          "schema_enum",
+          "undeclared_property",
+          "credential_field",
+          "credential_value"
+        ],
+        "type": "string"
+      }
+    },
+    "required": [
+      "error",
+      "reason",
+      "message"
+    ],
+    "type": "object"
+  }
+]

removedOutput schema / properties

Removed value: -{
-  "balance_units": {
-    "description": "Remaining balance units after this request (only present when balance is known and x-bv-meter: 1 was sent).",
-    "type": "integer"
-  },
-  "cu_charged": {
-    "description": "Compute Units billed for this request (only present when charged and x-bv-meter: 1 was sent).",
-    "type": "integer"
-  },
-  "error": {
-    "properties": {
-      "code": {
-        "type": "number"
-      },
-      "docs_url": {
-        "type": [
-          "string",
-          "null"
-        ]
-      },
-      "message": {
-        "type": "string"
-      },
-      "reason": {
-        "type": [
-          "string",
-          "null"
-        ]
-      }
-    },
-    "type": [
-      "object",
-      "string"
-    ]
-  },
-  "help": {
-    "properties": {
-      "guide_url": {
-        "type": "string"
-      },
-      "tool": {
-        "type": "string"
-      }
-    },
-    "type": "object"
-  },
-  "id": {
-    "type": [
-      "number",
-      "string",
-      "null"
-    ]
-  },
-  "jsonrpc": {
-    "type": "string"
-  },
-  "message": {
-    "type": "string"
-  },
-  "result": {},
-  "signup_url": {
-    "description": "Registration and sign-up URL (returned when rate-limited on the public endpoint).",
-    "type": "string"
-  }
-}

Changed1 schema field changedOct 10, 2026

changedInput schema / properties / chain / description

Previous value: -"Target blockchain network slug (e.g. 'robinhood_mainnet'). Must exist in GET /v1/chains."New value: +"Target blockchain network slug (e.g. 'base_mainnet'). Must exist in GET /v1/chains; list_chains returns the valid slugs."

Changed4 schema fields changedOct 4, 2026

changedInput schema / properties / method / description

Previous value: -"JSON-RPC 2.0 method name (e.g. 'eth_blockNumber', 'eth_call', 'eth_getLogs')."New value: +"JSON-RPC 2.0 method name (e.g. 'eth_blockNumber', 'eth_call', 'eth_getLogs'). Write methods are not accepted."

changedOutput schema / properties / error / type

Previous value: -"object"New value: +[
+  "object",
+  "string"
+]

addedOutput schema / properties / help

Added value: +{
+  "properties": {
+    "guide_url": {
+      "type": "string"
+    },
+    "tool": {
+      "type": "string"
+    }
+  },
+  "type": "object"
+}

addedOutput schema / properties / message
```
Added value: +{
+  "type": "string"
+}
```

Changed1 schema field changedOct 3, 2026

addedOutput schema / properties / signup_url

Added value: +{
+  "description": "Registration and sign-up URL (returned when rate-limited on the public endpoint).",
+  "type": "string"
+}

Changed2 schema fields changedOct 2, 2026

addedOutput schema / properties / balance_units

Added value: +{
+  "description": "Remaining balance units after this request (only present when balance is known and x-bv-meter: 1 was sent).",
+  "type": "integer"
+}

addedOutput schema / properties / cu_charged

Added value: +{
+  "description": "Compute Units billed for this request (only present when charged and x-bv-meter: 1 was sent).",
+  "type": "integer"
+}

AddedOct 1, 2026

TDQS

A4.9/5.0

Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already cover readOnlyHint and openWorldHint, and the description still adds substantive context: the keyless fallback path `/v1/{chain}/public`, its restriction to the chain's `public.methods` allowlist, the auth header mechanism ('x-api-key' or Bearer), and the warning that keys must never be passed as tool parameters. That is real behavioral disclosure beyond structured data.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The operation and its scope are front-loaded in the first clause, and each following sentence carries a distinct constraint (chain naming, keyless path, write-method exclusion, auth placement, references). Documentation links are the only borderline filler and they serve a real lookup need for method semantics.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return details are not required, yet the description still notes that the raw JSON-RPC server response is returned. Auth requirements, fallback behavior, and the write-method boundary are all covered, leaving nothing an agent needs in order to invoke this correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3. The description still adds orientation: chain slugs come from list_chains and follow the 'base_mainnet' shape, method must be a non-write JSON-RPC name, and params is the optional positional array defaulting to []. It stops short of adding syntax detail the schema lacks, so it earns 4 rather than 5.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Execute a read-only JSON-RPC 2.0 method on a specified blockchain network') and immediately scopes what it does not do (write methods). This clearly separates it from the sibling send_raw_transaction without opening either schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly names the alternative for write operations ('use send_raw_transaction instead') and lays out the conditional branches: keyless endpoint when no API key is configured, full access with a key. It also points to list_chains for valid slugs and external specs for method semantics.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

All BlockVectra: multi-chain RPC & Data API tools Inspect

Try in Browser

One endpoint for every MCP toolRayrun runs every MCP server behind one URL and holds the credentials. Each call is decided per client, tool, and argument, then recorded.ray.runAd

Glama MCP Gateway

Add one secure layer between your agents and this server.