add_observationsAttach new observations to existing knowledge graph entities so persistent memory can store updated user facts across chats.
Add new observations to existing entities in the knowledge graph
| Name | Required | Description | Default |
|---|---|---|---|
| observations | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
| results | Yes |
Changes observed during successful MCP inspections.
Input schema / $schemaAdded value: +"http://json-schema.org/draft-07/schema#"Output schema / (root)Previous value: -nullNew value: +{
+ "$schema": "http://json-schema.org/draft-07/schema#",
+ "additionalProperties": false,
+ "properties": {
+ "results": {
+ "items": {
+ "additionalProperties": false,
+ "properties": {
+ "addedObservations": {
+ "items": {
+ "type": "string"
+ },
+ "type": "array"
+ },
+ "entityName": {
+ "type": "string"
+ }
+ },
+ "required": [
+ "entityName",
+ "addedObservations"
+ ],
+ "type": "object"
+ },
+ "type": "array"
+ }
+ },
+ "required": [
+ "results"
+ ],
+ "type": "object"
+}v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations cover the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false, openWorldHint=false), so the description need not restate that this is a non-destructive write. It adds one piece of context beyond the annotations - additions target existing entities - but stays silent on whether duplicates are appended or deduplicated, which matters given idempotentHint=false, and on failure behavior for unknown entity names.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
A single front-loaded sentence with no filler. It is appropriately sized for the operation, though the brevity doubles as under-specification rather than pure economy.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
An output schema exists, so return values need not be explained. However, for a non-idempotent mutation with an undocumented nested parameter shape, the description should say more about duplicate handling, entity-not-found behavior, and batch semantics to be complete.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 0% at the top level; the sole 'observations' parameter is an array of objects with no description, and the description does not explain its structure or the entityName/contents pairing. The schema at least documents the nested fields, but the description does nothing to compensate for the coverage gap.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
Clear verb+resource: adds observation contents to entities in the knowledge graph. It also constrains scope to 'existing entities.' It does not explicitly contrast itself with siblings like create_entities or delete_observations, but the resource overlap is small enough to be inferable.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The phrase 'existing entities' implies a precondition (the entity must already exist) but never states it as a rule, nor what to do otherwise. No alternative is named, so an agent must infer that create_entities is for new entities and delete_observations for removal.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.