signal_layer_catalogFree inventory returning service, version, defaultEntryPoint and the four actionable primitives with capabilities and prices; the catalog tool itself is omitted. This is not a task router. If the correct tool is uncertain, prefer signal_layer_router.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
| Name | Required | Description | Default |
|---|---|---|---|
| tools | No | ||
| service | No | ||
| version | No | ||
| defaultEntryPoint | No |
Changes observed during successful MCP inspections.
Output schema / (root)Previous value: -nullNew value: +{
+ "$schema": "https://json-schema.org/draft/2020-12/schema",
+ "additionalProperties": {},
+ "properties": {
+ "defaultEntryPoint": {
+ "type": "string"
+ },
+ "service": {
+ "type": "string"
+ },
+ "tools": {
+ "items": {},
+ "type": "array"
+ },
+ "version": {
+ "type": "string"
+ }
+ },
+ "type": "object"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already cover read-only, idempotent, non-destructive, closed-world behavior, so the safety profile is handled. The description adds genuinely new context: the call is free, and the catalog tool itself is omitted from the returned list — a non-obvious output quirk. It does not mention auth or rate limits, so it falls just short of 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?
Front-loaded with the inventory contents, then the two routing sentences. The first sentence is dense and slightly run-on, but every clause carries information (fields returned, prices, self-omission) and nothing is padding.
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 spelled out, yet the description helpfully previews the key ones. With annotations covering safety and no parameters to document, there is no gap an agent would need filled before calling this tool.
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?
Zero parameters, so the baseline of 4 applies; there is no parameter semantics to explain and the description correctly spends no space on them.
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+resource (free inventory/catalog) and enumerates exactly what it returns: service, version, defaultEntryPoint, and the four actionable primitives with capabilities and prices. It explicitly separates itself from the sibling signal_layer_router ('This is not a task router'), so an agent can choose between them without opening either schema.
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 an explicit negative condition ('not a task router') and names the alternative to use when the right tool is uncertain ('prefer signal_layer_router'). That is a concrete when-not plus routing rule, not implied usage.
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.