mcp-notion-fast

Update block

update_block

Idempotent

Update any Notion block by submitting a validated JSON patch. Provide block ID and payload to modify content and properties.

Instructions

Update a Notion block using a validated JSON object payload.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "blockId": "<blockId>",
      "patch": "<patch>"
    },
    "name": "update_block"
  }
}

Input Schema

Name	Required	Description	Default
`patch`	Yes
`blockId`	Yes

Output Schema

Name	Required	Description	Default
`ok`	Yes
`code`	No
`data`	No
`error`	No
`status`	No

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Aug 3, 2026

TDQS

B3/5.0

Behavior3/5

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

Annotations already declare readOnlyHint=false and destructiveHint=false, and the description does not contradict them. The phrase 'validated JSON object payload' adds a small bit of behavioral context beyond the schema, but it does not disclose side effects, permissions, or error handling. Since annotations cover the safety profile, this is acceptable but not rich.

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 description is a single, front-loaded sentence with no filler. Every word contributes to stating the operation and the payload requirement, making it highly concise and well-structured.

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

Completeness2/5

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

While an output schema exists, the description lacks contextual details such as what kind of updates are supported (partial vs. full), how the patch should be structured for different block types, and when to use this tool over update_page. Given the tool's moderate complexity with a nested object parameter, this description is incomplete.

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

Parameters2/5

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

Schema description coverage is 0%, so the description must compensate by explaining parameters. It mentions 'JSON object payload' which refers to the 'patch' parameter, but it does not explain the structure or accepted fields, nor does it mention 'blockId'. The minimal hint is insufficient for the patch object's arbitrary schema.

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

Purpose4/5

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

The description clearly states the action ('Update') and the resource ('Notion block'), making the tool's purpose understandable. However, it does not explicitly distinguish this tool from its sibling tools like update_page or delete_block, so it lacks sibling differentiation.

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

Usage Guidelines2/5

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

The description provides no guidance on when to use this tool versus alternatives such as update_page or get_block. There is no mention of prerequisites, scenarios, or when not to use it, leaving the agent without any usage direction.

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

Deploy Server