Skip to main content
Glama
mshegolev

mshegolev/prometheus-mcp

alertmanager_list_silences

Read-onlyIdempotent

Retrieve all Alertmanager silences with matchers, status, creator, and comment. Quickly identify which alerts are silenced and why, especially critical during incident handoffs.

Instructions

List all silences from Alertmanager.

Wraps GET /api/v2/silences. Returns silences with matchers, status (active/pending/expired), creator, comment, and time bounds.

Use this to understand which alerts are currently silenced and why. During incident handoffs, knowing what's silenced is critical — a silenced alert is invisible in Prometheus /alerts.

Examples: - Use when: "Is the HighCPU alert silenced?" → search silences for matching matchers. - Use when: "Who silenced alerts for the payment service?" → check createdBy and comment. - Don't use when: You want active firing alerts (call alertmanager_list_alerts).

Returns: dict with total_count / active_count / pending_count / expired_count / silences (list with matchers, status, etc.).

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
instanceNo
instancesNo

Output Schema

TableJSON Schema
NameRequiredDescriptionDefault
silencesYes
total_countYes
active_countYes
expired_countYes
pending_countYes
Behavior4/5

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

Annotations already declare readOnlyHint=true and destructiveHint=false, indicating a safe read operation. The description adds context that a silenced alert is invisible in Prometheus /alerts, which is useful behavioral insight. However, it does not mention potential edge cases like pagination 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?

The description is well-structured with a clear opening statement, the API endpoint, return details, usage guidance, and examples. Every sentence adds value, and it is appropriately brief for the tool's complexity.

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

Completeness3/5

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

Given the tool's simplicity (2 optional params, no required, has output schema), the description covers purpose, usage, and return values adequately. However, the lack of parameter semantics creates a notable gap, making it slightly incomplete.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters1/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, meaning the parameters 'instance' and 'instances' are undocumented in the schema. The description fails to explain these optional parameters or how they affect the query, leaving the agent without guidance on filtering by instance.

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?

The description explicitly states 'List all silences from Alertmanager' with a clear verb and resource. It differentiates from sibling tool alertmanager_list_alerts by noting when not to use it, ensuring no confusion.

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?

Provides explicit when-to-use scenarios with concrete examples ('Is the HighCPU alert silenced?') and a clear don't-use case ('Don't use when: You want active firing alerts (call alertmanager_list_alerts)'). This guides the agent effectively.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Install Server

Other Tools

Latest Blog Posts

MCP directory API

We provide all the information about MCP servers via our MCP API.

curl -X GET 'https://glama.ai/api/mcp/v1/servers/mshegolev/prometheus-mcp'

If you have feedback or need assistance with the MCP directory API, please join our Discord server