MCP GeneLab Server

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get_node_metadata

Read-onlyIdempotent

Retrieve metadata for all MetaNode nodes in the NASA GeneLab Knowledge Graph to inspect node properties and support spaceflight experiment analysis.

Instructions

Get metadata for all nodes from MetaNode nodes in the knowledge graph.

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {},
    "name": "get_node_metadata"
  }
}

Input Schema

Name	Required	Description	Default
`session_id`	No	Session id returned by `create_session()`. This server serves many users from one process; the session id is what keeps your output directory and generated plots private to you. Pass the SAME value on every tool call. If the server replies that the session is unknown or expired, call `create_session()` again and use the new id.

Schema Changelog

Changes observed during successful MCP inspections.

Changed2 schema fields changedv1.0.0Oct 16, 2026

addedInput schema / properties / session_id

Added value: +{
+  "anyOf": [
+    {
+      "type": "string"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "description": "Session id returned by `create_session()`. This server serves many users from one process; the session id is what keeps your output directory and generated plots private to you. Pass the SAME value on every tool call. If the server replies that the session is unknown or expired, call `create_session()` again and use the new id.",
+  "title": "Session Id"
+}

changedOutput schema / (root)

Previous value: -{
-  "$defs": {
-    "Annotations": {
-      "additionalProperties": true,
-      "properties": {
-        "audience": {
-          "anyOf": [
-            {
-              "items": {
-                "enum": [
-                  "user",
-                  "assistant"
-                ],
-                "type": "string"
-              },
-              "type": "array"
-            },
-            {
-              "type": "null"
-            }
-          ],
-          "default": null,
-          "title": "Audience"
-        },
-        "priority": {
-          "anyOf": [
-            {
-              "maximum": 1,
-              "minimum": 0,
-              "type": "number"
-            },
-            {
-              "type": "null"
-            }
-          ],
-          "default": null,
-          "title": "Priority"
-        }
-      },
-      "title": "Annotations",
-      "type": "object"
-    },
-    "TextContent": {
-      "additionalProperties": true,
-      "description": "Text content for a message.",
-      "properties": {
-        "_meta": {
-          "anyOf": [
-            {
-              "additionalProperties": true,
-              "type": "object"
-            },
-            {
-              "type": "null"
-            }
-          ],
-          "default": null,
-          "title": "Meta"
-        },
-        "annotations": {
-          "anyOf": [
-            {
-              "$ref": "#/$defs/Annotations"
-            },
-            {
-              "type": "null"
-            }
-          ],
-          "default": null
-        },
-        "text": {
-          "title": "Text",
-          "type": "string"
-        },
-        "type": {
-          "const": "text",
-          "title": "Type",
-          "type": "string"
-        }
-      },
-      "required": [
-        "type",
-        "text"
-      ],
-      "title": "TextContent",
-      "type": "object"
-    }
-  },
-  "properties": {
-    "result": {
-      "items": {
-        "$ref": "#/$defs/TextContent"
-      },
-      "title": "Result",
-      "type": "array"
-    }
-  },
-  "required": [
-    "result"
-  ],
-  "title": "get_node_metadataOutput",
-  "type": "object"
-}New value: +null

First observedv0.4.0May 29, 2026

TDQS

B3.2/5.0

Behavior3/5

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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint=false, so safety/behavior is covered by structured data. The description adds only a scope hint ('all nodes'), with no disclosure of pagination, return shape, or size limits, so it is merely adequate given the annotation coverage.

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?

A single front-loaded sentence with no filler. It is efficient, though the awkward 'nodes from MetaNode nodes' phrasing slightly undercuts clarity.

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

Completeness3/5

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

For a simple rea d-only tool with annotations and no output schema, the definition is minimally viable. It does not explain what metadata is returned or what a 'MetaNode' is, which an agent would need to interpret results.

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?

With schema coverage at 100% and a single optional session_id fully documented in the schema, the baseline of 3 applies. The description provides no additional parameter meaning beyond what the schema already states.

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?

States a specific verb (Get) and resource (metadata for nodes) with a scope qualifier ('all nodes'). However, the phrase 'from MetaNode nodes' introduces unexplained jargon and the description never names the closely-related sibling get_relationship_metadata or get_neo4j_schema, so sibling differentiation is only implicit.

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?

No when-to-use guidance is given. Nothing indicates when an agent should call this versus get_relationship_metadata, get_neo4j_schema, or query, and no prerequisites are stated.

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