Control Plane

List & Discover Metrics

list_metrics

Read-onlyIdempotent

Metric names and labels you can query before query_metrics. Returns the documented default metrics with a PromQL template each, plus every series present in the org now (custom metrics, kube_/node_). filter narrows by substring; metric returns that metric's live label values. Call it when a query returns nothing or a name is uncertain.

Input Schema

TableJSON Schema

Name	Required	Description
`org`	No	Organization slug.
`limit`	No	Maximum number of items to return (1-500, default: all).
`filter`	No	Case-insensitive substring to narrow the catalog and live metric names (e.g. "cpu", "workload", "agent").
`metric`	No	A metric name to ground: returns its REAL label dimensions and sample values (workload, gvc, location, …) from live data, so you can build an accurate PromQL filter. Works for custom metrics too.

Output Schema

TableJSON Schema

Name	Required	Description
`ok`	Yes
`data`	No	The full result. Read this, not only the summary.
`details`	No
`summary`	Yes
`nextSteps`	No

Schema Changelog

Changes observed during successful MCP inspections.

Changed14 schema fields changedSep 30, 2026

removedInput schema / $schema

Removed value: -"http://json-schema.org/draft-07/schema#"

removedInput schema / additionalProperties
```
Removed value: -false
```

changedInput schema / properties / org / description

Previous value: -"Organization slug (lowercase kebab-case). NEVER guess — if the user has not named one, ask. On org-not-found, stop and ask; do not retry variants."New value: +"Organization slug."

removedInput schema / properties / org / maxLength
```
Removed value: -63
```
removedInput schema / properties / org / minLength
```
Removed value: -1
```

removedInput schema / properties / org / pattern

Removed value: -"^[a-z0-9]([a-z0-9-]{0,61}[a-z0-9])?$"

removedInput schema / required
```
Removed value: -[
-  "org"
-]
```

removedOutput schema / $schema

Removed value: -"http://json-schema.org/draft-07/schema#"

removedOutput schema / additionalProperties
```
Removed value: -false
```

changedOutput schema / properties / data / description

Previous value: -"The full machine-readable result — list rows, the resource object, query results. Read THIS, not just the summary."New value: +"The full result. Read this, not only the summary."

addedOutput schema / properties / details
```
Added value: +{
+  "type": "string"
+}
```

removedOutput schema / properties / nextSteps / description

Removed value: -"Recommended follow-up actions for this task, in order."

removedOutput schema / properties / ok / description
```
Removed value: -"Whether the call succeeded."
```
removedOutput schema / properties / summary / description
```
Removed value: -"One-line summary of the result."
```

First observedJun 28, 2026

TDQS

A4.5/5.0

Behavior4/5

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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description still adds real behavioral context: it returns documented default metrics each with a PromQL template, plus all live org series, and that `metric` grounds real label dimensions. It stops short of noting auth or rate limits.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Four tight sentences, front-loaded with what the tool returns, then how the two key params narrow it, then the call condition. No filler or repetition.

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

Completeness5/5

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

With an output schema present, return values need not be explained, and the description covers the remaining agent needs: scope (default + live series), narrowing behavior, and the decision point for calling it. Nothing material is missing.

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?

Schema coverage is 100%, so both `filter` and `metric` are already documented in the schema with examples and semantics. The description's restatement ('filter narrows by substring', 'metric returns live label values') largely duplicates that, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource (list/discover metric names and labels) and explicitly positions itself relative to the sibling `query_metrics`, which it precedes. An agent can distinguish discovery from querying 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.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives an explicit trigger condition — 'Call it when a query returns nothing or a name is uncertain' — and names the alternative (`query_metrics`) it feeds into. This is exactly the when/when-not/alternative structure 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.

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