get_user_by_idRead a public Synoptic profile by user ID. Use get_user for a username, or get_me for the signed-in account. Unknown IDs return User not found.
| Name | Required | Description | Default |
|---|---|---|---|
| userId | Yes | Synoptic user ID, such as a stream’s authorId or an id from get_followers |
| Name | Required | Description | Default |
|---|---|---|---|
| user | Yes |
Changes observed during successful MCP inspections.
Output schema / properties / user / properties / medalsCountRemoved value: -{
- "type": "number"
-}Output schema / properties / user / requiredPrevious value: -[
- "id",
- "username",
- "fullName",
- "createdAt",
- "followingCount",
- "followersCount",
- "medalsCount",
- "isHighlighted"
-]New value: +[
+ "id",
+ "username",
+ "fullName",
+ "createdAt",
+ "followingCount",
+ "followersCount",
+ "isHighlighted"
+]Output schema / properties / user / properties / avatar / anyOfPrevious value: -[
- {
- "additionalProperties": false,
- "properties": {
- "bucket": {
- "description": "S3 bucket holding the image",
- "minLength": 1,
- "type": "string"
- },
- "height": {
- "anyOf": [
- {
- "exclusiveMinimum": 0,
- "type": "integer"
- },
- {
- "type": "null"
- }
- ],
- "description": "Height in pixels"
- },
- "key": {
- "description": "Storage key of the image",
- "minLength": 1,
- "type": "string"
- },
- "region": {
- "description": "AWS region of the bucket",
- "minLength": 1,
- "type": "string"
- },
- "type": {
- "description": "MIME type, such as image/png",
- "minLength": 1,
- "type": "string"
- },
- "width": {
- "anyOf": [
- {
- "exclusiveMinimum": 0,
- "type": "integer"
- },
- {
- "type": "null"
- }
- ],
- "description": "Width in pixels"
- }
- },
- "required": [
- "bucket",
- "key",
- "region",
- "type"
- ],
- "type": "object"
- },
- {
- "type": "null"
- }
-]New value: +[
+ {
+ "additionalProperties": false,
+ "properties": {
+ "bucket": {
+ "minLength": 1,
+ "type": "string"
+ },
+ "height": {
+ "anyOf": [
+ {
+ "exclusiveMinimum": 0,
+ "type": "integer"
+ },
+ {
+ "type": "null"
+ }
+ ]
+ },
+ "key": {
+ "minLength": 1,
+ "type": "string"
+ },
+ "region": {
+ "minLength": 1,
+ "type": "string"
+ },
+ "type": {
+ "description": "MIME type, such as image/png",
+ "minLength": 1,
+ "type": "string"
+ },
+ "width": {
+ "anyOf": [
+ {
+ "exclusiveMinimum": 0,
+ "type": "integer"
+ },
+ {
+ "type": "null"
+ }
+ ]
+ }
+ },
+ "required": [
+ "bucket",
+ "key",
+ "region",
+ "type"
+ ],
+ "type": "object"
+ },
+ {
+ "type": "null"
+ }
+]Output schema / properties / user / properties / backgroundImage / anyOfPrevious value: -[
- {
- "additionalProperties": false,
- "properties": {
- "bucket": {
- "description": "S3 bucket holding the image",
- "minLength": 1,
- "type": "string"
- },
- "height": {
- "anyOf": [
- {
- "exclusiveMinimum": 0,
- "type": "integer"
- },
- {
- "type": "null"
- }
- ],
- "description": "Height in pixels"
- },
- "key": {
- "description": "Storage key of the image",
- "minLength": 1,
- "type": "string"
- },
- "region": {
- "description": "AWS region of the bucket",
- "minLength": 1,
- "type": "string"
- },
- "type": {
- "description": "MIME type, such as image/png",
- "minLength": 1,
- "type": "string"
- },
- "width": {
- "anyOf": [
- {
- "exclusiveMinimum": 0,
- "type": "integer"
- },
- {
- "type": "null"
- }
- ],
- "description": "Width in pixels"
- }
- },
- "required": [
- "bucket",
- "key",
- "region",
- "type"
- ],
- "type": "object"
- },
- {
- "type": "null"
- }
-]New value: +[
+ {
+ "additionalProperties": false,
+ "properties": {
+ "bucket": {
+ "minLength": 1,
+ "type": "string"
+ },
+ "height": {
+ "anyOf": [
+ {
+ "exclusiveMinimum": 0,
+ "type": "integer"
+ },
+ {
+ "type": "null"
+ }
+ ]
+ },
+ "key": {
+ "minLength": 1,
+ "type": "string"
+ },
+ "region": {
+ "minLength": 1,
+ "type": "string"
+ },
+ "type": {
+ "description": "MIME type, such as image/png",
+ "minLength": 1,
+ "type": "string"
+ },
+ "width": {
+ "anyOf": [
+ {
+ "exclusiveMinimum": 0,
+ "type": "integer"
+ },
+ {
+ "type": "null"
+ }
+ ]
+ }
+ },
+ "required": [
+ "bucket",
+ "key",
+ "region",
+ "type"
+ ],
+ "type": "object"
+ },
+ {
+ "type": "null"
+ }
+]Input schema / properties / userId / descriptionAdded value: +"Synoptic user ID, such as a stream’s authorId or an id from get_followers"Output schema / properties / user / properties / avatar / anyOfPrevious value: -[
- {
- "additionalProperties": false,
- "properties": {
- "bucket": {
- "minLength": 1,
- "type": "string"
- },
- "height": {
- "anyOf": [
- {
- "exclusiveMinimum": 0,
- "type": "integer"
- },
- {
- "type": "null"
- }
- ]
- },
- "key": {
- "minLength": 1,
- "type": "string"
- },
- "region": {
- "minLength": 1,
- "type": "string"
- },
- "type": {
- "minLength": 1,
- "type": "string"
- },
- "width": {
- "anyOf": [
- {
- "exclusiveMinimum": 0,
- "type": "integer"
- },
- {
- "type": "null"
- }
- ]
- }
- },
- "required": [
- "bucket",
- "key",
- "region",
- "type"
- ],
- "type": "object"
- },
- {
- "type": "null"
- }
-]New value: +[
+ {
+ "additionalProperties": false,
+ "properties": {
+ "bucket": {
+ "description": "S3 bucket holding the image",
+ "minLength": 1,
+ "type": "string"
+ },
+ "height": {
+ "anyOf": [
+ {
+ "exclusiveMinimum": 0,
+ "type": "integer"
+ },
+ {
+ "type": "null"
+ }
+ ],
+ "description": "Height in pixels"
+ },
+ "key": {
+ "description": "Storage key of the image",
+ "minLength": 1,
+ "type": "string"
+ },
+ "region": {
+ "description": "AWS region of the bucket",
+ "minLength": 1,
+ "type": "string"
+ },
+ "type": {
+ "description": "MIME type, such as image/png",
+ "minLength": 1,
+ "type": "string"
+ },
+ "width": {
+ "anyOf": [
+ {
+ "exclusiveMinimum": 0,
+ "type": "integer"
+ },
+ {
+ "type": "null"
+ }
+ ],
+ "description": "Width in pixels"
+ }
+ },
+ "required": [
+ "bucket",
+ "key",
+ "region",
+ "type"
+ ],
+ "type": "object"
+ },
+ {
+ "type": "null"
+ }
+]Output schema / properties / user / properties / avatar / descriptionAdded value: +"Profile image; null when none is set"Output schema / properties / user / properties / backgroundImage / anyOfPrevious value: -[
- {
- "$ref": "#/properties/user/properties/avatar/anyOf/0"
- },
- {
- "type": "null"
- }
-]New value: +[
+ {
+ "additionalProperties": false,
+ "properties": {
+ "bucket": {
+ "description": "S3 bucket holding the image",
+ "minLength": 1,
+ "type": "string"
+ },
+ "height": {
+ "anyOf": [
+ {
+ "exclusiveMinimum": 0,
+ "type": "integer"
+ },
+ {
+ "type": "null"
+ }
+ ],
+ "description": "Height in pixels"
+ },
+ "key": {
+ "description": "Storage key of the image",
+ "minLength": 1,
+ "type": "string"
+ },
+ "region": {
+ "description": "AWS region of the bucket",
+ "minLength": 1,
+ "type": "string"
+ },
+ "type": {
+ "description": "MIME type, such as image/png",
+ "minLength": 1,
+ "type": "string"
+ },
+ "width": {
+ "anyOf": [
+ {
+ "exclusiveMinimum": 0,
+ "type": "integer"
+ },
+ {
+ "type": "null"
+ }
+ ],
+ "description": "Width in pixels"
+ }
+ },
+ "required": [
+ "bucket",
+ "key",
+ "region",
+ "type"
+ ],
+ "type": "object"
+ },
+ {
+ "type": "null"
+ }
+]Output schema / properties / user / properties / backgroundImage / descriptionAdded value: +"Profile background image; null when none is set"Output schema / properties / user / properties / followersCount / descriptionAdded value: +"Users following this user"Output schema / properties / user / properties / followingCount / descriptionAdded value: +"Users this user follows; excludes streams"Output schema / properties / user / properties / id / descriptionAdded value: +"Synoptic user ID for follow_user, is_following_user or get_user_by_id"Output schema / properties / user / properties / isHighlighted / descriptionAdded value: +"Featured by Synoptic; listed by get_highlighted_authors"Output schema / properties / user / properties / xComHandle / descriptionAdded value: +"Verified X handle linked to this profile, without @"Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is covered. The description adds genuinely new behavior: the profile returned is the "public" one, and unknown IDs produce a "User not found" error — useful failure-mode disclosure. It stops short of richer context (rate limits, visibility restrictions on private accounts), so not a 5.
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?
Three short sentences, no waste. The core purpose is front-loaded and the disambiguation and error note follow in priority order.
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 no explanation, and the annotations carry the safety profile. With the param fully documented and the error case called out, an agent has everything needed to call this correctly.
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 coverage is 100% and the userId schema entry already explains what a Synoptic user ID is and where to get one (stream authorId, get_followers). The description adds no format or syntax detail beyond the schema, so the baseline 3 applies.
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?
States a specific verb and resource ("Read a public Synoptic profile") plus the lookup key (user ID). It distinguishes itself from get_user and get_me by naming them explicitly, so an agent can route without opening schemas.
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?
Gives explicit alternatives and the condition selecting each: get_user for a username, get_me for the signed-in account, this tool for a raw user ID. This is exactly the when/when-not routing guidance the dimension asks for.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.