Add new observations to existing entities in the knowledge graph
AI agents use add_observations to create or update resources in MCP Neo4j Knowledge Graph Memory Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your MCP Neo4j Knowledge Graph Memory Server environment.
This tool creates or appends new observational data to existing entities in a Neo4j knowledge graph. This is a reversible write operation—observations can be added without permanently destroying data (distinguishing it from the 'delete_observations' sibling tool). It does not execute arbitrary code, move money, or irreversibly delete data.
From the tool's definition Tool name 'add_observations' and description 'Add new observations to existing entities' indicate creation/addition of data to the knowledge graph. The verb 'Add' directly signals data modification rather than retrieval, deletion, or code execution.
Documented attack patterns abuse exactly the kind of access add_observations gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and MCP Neo4j Knowledge Graph Memory Server, and nothing reaches the server without passing your rules. This is the rule we recommend for add_observations:
{
"version": "1",
"default": "deny",
"tools": {
"add_observations": {
"limits": [
{
"counter": "add_observations_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
} add_observations stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.
Free to start. No card required.
Add new observations to existing entities in the knowledge graph. It is categorised as a Write tool in the MCP Neo4j Knowledge Graph Memory Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the MCP Neo4j Knowledge Graph Memory Server MCP server in PolicyLayer and add a rule for add_observations: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches MCP Neo4j Knowledge Graph Memory Server. Nothing to install.
add_observations is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the add_observations rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for add_observations. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
add_observations is provided by the MCP Neo4j Knowledge Graph Memory Server MCP server (jovanhsu/mcp-neo4j-memory-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from MCP Neo4j Knowledge Graph Memory Server, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
8 MCP Neo4j Knowledge Graph Memory Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.