Run instant PromQL queries to investigate request failures and monitor metrics without opening Grafana.
Run an instant PromQL query, for example sum(rate(http_requests_total[5m])).
| Name | Required | Description | Default |
|---|---|---|---|
| query | Yes | ||
| session_name | No | default |
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description alone must convey behavior. It only mentions 'instant' but does not disclose potential side effects, authentication requirements, or error handling. It does not clarify whether a session must be established first or what happens on invalid queries.
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 sentence with an example, which is concise and immediately understandable. However, it could be slightly more informative without becoming verbose.
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?
Given the presence of connection-related sibling tools, the description lacks essential context about session management. It also does not mention what the output looks like, despite having an output schema. An agent might not know if a connection is required 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?
The description explains the `query` parameter with an example, but the `session_name` parameter is entirely unexplained. Since the schema provides no descriptions either, the agent is left guessing about session_name's purpose and relationship to the connection tools.
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 clearly states the action ('Run an instant PromQL query') and provides a concrete example, making the purpose unambiguous. It also differentiates from sibling tools like obs_query_logs and obs_get_trace by focusing on metrics queries.
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?
No guidance is given on when to use this tool versus alternatives like obs_query_logs or obs_get_trace. There is no mention of prerequisites such as needing an active connection (given the sibling obs_connect/obs_disconnect) or when this is the appropriate choice.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.