Generate tuning recommendations for a single query from history using EXPLAIN, plan cache statistics, and table design. Identify bottlenecks and improve SQL performance.
Tuning recommendations for one query from the history (EXPLAIN, plan cache statistics, table design).
| Name | Required | Description | Default |
|---|---|---|---|
| key | Yes |
Changes observed during successful MCP inspections.
v0.8.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
readOnlyHint=true already tells the agent this is a safe read. The description adds useful context by naming the analysis content returned (EXPLAIN, plan cache statistics, table design), but says nothing about permissions, cost, or how the key is obtained.
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?
A single, front-loaded sentence with the core purpose stated first and details in parentheses. No wasted text, though it could carry slightly more load given the gaps elsewhere.
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?
With no output schema, the description usefully hints at the return content, and the readOnly annotation covers safety. However, for a tool whose only input is an undocumented key, it leaves the agent without enough 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?
Schema description coverage is 0% for the single 'key' parameter. The phrase 'one query from the history' only loosely implies that key identifies a query; it provides no format, source, or example, so the description fails to compensate for the coverage gap.
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: 'Tuning recommendations for one query from the history'. The parenthetical names the concrete artifacts returned (EXPLAIN, plan cache statistics, table design). It does not explicitly distinguish itself from siblings like query_history_advisor or query_advisor_report, so it's clear but not differentiated.
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?
There is no when-to-use guidance and no mention of alternatives, despite several closely related siblings (query_history_advisor, query_advisor_report, query_history_ask). Only the implicit 'one query from the history' scope hints at usage.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.