mssql_buffer_hit_ratioCalculates SQL Server buffer cache hit ratio percentage to detect memory pressure; ratios below 95% indicate too little memory for the workload.
Buffer cache hit ratio (%). Below 95% suggests too little memory for the workload.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds genuine analytical context with the 95% threshold, but omits the scope of the measurement (instance-wide vs per-database) and any note on what the returned value looks like.
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?
Two short sentences with no padding, and the metric definition is front-loaded. It is arguably too terse rather than too long, but nothing is wasted.
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 and no parameters, the description carries the burden of explaining the returned value and its scope. The threshold guidance is helpful, but the granularity of the ratio (per instance, per database, or cached-plan scope) is never stated, leaving a real gap for a diagnostic 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 tool takes zero parameters, so the schema is trivially complete and the description has nothing to compensate for. Per the rubric, a zero-parameter tool gets the baseline of 4.
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 names a specific metric ('Buffer cache hit ratio (%)'), so an agent knows exactly what this tool returns. It does not, however, differentiate from related diagnostic siblings such as mssql_memory_pressure or mssql_disk_io_latency, which an agent might reasonably confuse with it.
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 statement of when to use this tool versus alternatives. The interpretive threshold ('Below 95% suggests too little memory') hints at a diagnostic purpose but never routes the agent to mssql_memory_pressure or any other sibling, and no prerequisites are given.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.