list_instancesList the caller's AgentsPodium instances (agents): id, name, engine, tier, status, endpoint and A2A URL, domain, creation date. Never returns secrets.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
| Name | Required | Description | Default |
|---|---|---|---|
| instances | Yes | The caller's instances. |
Changes observed during successful MCP inspections.
Output schema / (root)Previous value: -nullNew value: +{
+ "$schema": "http://json-schema.org/draft-07/schema#",
+ "additionalProperties": false,
+ "properties": {
+ "instances": {
+ "description": "The caller's instances.",
+ "items": {
+ "additionalProperties": false,
+ "properties": {
+ "a2aUrl": {
+ "description": "A2A JSON-RPC endpoint for the instance, or null if A2A is not enabled.",
+ "type": [
+ "string",
+ "null"
+ ]
+ },
+ "createdAt": {
+ "description": "ISO timestamp when the instance was created.",
+ "type": "string"
+ },
+ "domain": {
+ "description": "Customer-owned domain serving the instance, or null.",
+ "type": [
+ "string",
+ "null"
+ ]
+ },
+ "endpointUrl": {
+ "description": "Public HTTPS endpoint for the instance, or null if not yet assigned.",
+ "type": [
+ "string",
+ "null"
+ ]
+ },
+ "engine": {
+ "description": "Runtime engine id (e.g. hermes).",
+ "type": "string"
+ },
+ "id": {
+ "description": "Instance (agent) id.",
+ "type": "string"
+ },
+ "name": {
+ "description": "Display name.",
+ "type": "string"
+ },
+ "status": {
+ "description": "Lifecycle status (e.g. running, stopped).",
+ "type": "string"
+ },
+ "tier": {
+ "description": "Hosting plan id.",
+ "type": "string"
+ }
+ },
+ "required": [
+ "id",
+ "name",
+ "engine",
+ "tier",
+ "status",
+ "endpointUrl",
+ "a2aUrl",
+ "domain",
+ "createdAt"
+ ],
+ "type": "object"
+ },
+ "type": "array"
+ }
+ },
+ "required": [
+ "instances"
+ ],
+ "type": "object"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The readOnlyHint annotation already signals a safe read operation, and the description adds useful behavioral context by explicitly listing the returned fields and stating that secrets are never returned. This security disclaimer goes beyond the structured annotation and helps set expectations.
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?
The description is a single well-structured sentence that front-loads the core operation and then lists the return fields. Every part earns its place, and the important 'Never returns secrets' caveat is included without bloat.
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?
For a parameterless read-only list tool with a provided output schema, the description is complete: it names the resource, scope, returned fields, and security boundary. Nothing essential is missing for an agent to invoke it 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?
The input schema has zero parameters, so the baseline of 4 applies. No parameter documentation is needed, and the description appropriately focuses on output rather than input semantics.
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?
The description uses a specific verb ('List') with a precise resource ('the caller's AgentsPodium instances') and enumerates the returned fields. It distinguishes this tool from siblings like list_platforms by clarifying it lists instances/agents, not platforms.
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 description does not explicitly say when to use this tool versus alternatives such as instance_health or list_platforms. While the operation is clear, there is no guidance about exclusions or conditions that should steer an agent to a sibling tool.
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.