Obsidian MCP Server

write_note

Create notes in Obsidian vaults for documentation, meeting notes, ideas, or content using markdown formatting, tags, and frontmatter.

Instructions

Write or create a note in the Obsidian vault. Can be used for documentation, meeting notes, ideas, or any other content.

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": {
      "path": "<path>",
      "content": "<content>"
    },
    "name": "write_note"
  }
}

Input Schema

Name	Required	Description
`path`	Yes	Relative path in vault (e.g., 'Projects/my-project/notes.md')
`title`	No	Note title (used in frontmatter)
`content`	Yes	Markdown content of the note
`tags`	No	Tags for the note
`frontmatter`	No	Additional frontmatter fields

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Jan 20, 2026

TDQS

C2.9/5.0

Behavior2/5

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool 'Write or create a note,' implying a write operation, but doesn't disclose critical behavioral traits such as whether it overwrites existing notes, requires specific permissions, handles errors, or has rate limits. The description adds minimal context beyond the basic action, leaving significant gaps for a mutation tool.

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

Conciseness4/5

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

The description is concise and front-loaded, stating the core purpose in the first sentence. The second sentence adds useful context without redundancy. Both sentences earn their place by clarifying the tool's function and providing examples, though it could be slightly more structured by explicitly mentioning key parameters or behavioral aspects.

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?

Given the tool's complexity (5 parameters, including nested objects, no output schema, and no annotations), the description is incomplete. It doesn't address behavioral traits like overwrite behavior, error handling, or output format, and lacks usage guidelines compared to siblings. For a write operation with multiple parameters and no structured safety hints, more comprehensive context is needed to adequately inform an agent.

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

Parameters3/5

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

Schema description coverage is 100%, meaning all parameters are documented in the input schema. The description adds no specific parameter semantics beyond implying general note creation. It doesn't explain interactions between parameters (e.g., how 'title' relates to 'path' or 'frontmatter'), so it provides no extra value over the schema. Baseline 3 is appropriate when the schema handles parameter documentation adequately.

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 tool's purpose: 'Write or create a note in the Obsidian vault.' It specifies the action (write/create) and resource (note in Obsidian vault), and provides examples of use cases (documentation, meeting notes, ideas). However, it doesn't explicitly differentiate from sibling tools like 'append_to_note' or 'write_session_report', which would require a 5.

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 mentions general use cases ('documentation, meeting notes, ideas, or any other content'), but provides no explicit guidance on when to use this tool versus alternatives. For example, it doesn't clarify when to choose 'write_note' over 'append_to_note' or 'write_session_report', nor does it mention prerequisites or exclusions. This lack of comparative context results in minimal guidance.

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

Deploy Server