Retrieve error rate trends for a Sentry project over a specified period, filtering by received, rejected, or blacklisted events to monitor issue volume.
Get error rate trends for a Sentry project over a time range.
| Name | Required | Description | Default |
|---|---|---|---|
| stat | No | received | |
| period | No | Lookback period (e.g., "7d", "14d") | 14d |
| project | Yes | Sentry project slug | |
| interval | No | 1d |
Changes observed during successful MCP inspections.
v3.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full behavioral burden, yet it discloses nothing about authentication, rate limits, cost, or return shape. It doesn't even state that this is a read-only operation, nor that the 'stat' selection changes what is returned.
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 no filler or redundancy. It is efficient, though the extreme brevity is part of why other dimensions are thin.
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?
For a 4-parameter tool with no annotations and no output schema, the description gives only the general return concept ('error rate trends'). It omits any explanation of what the enum parameters select and does not correct the fact that 'rejected'/'blacklisted' stats are not really error-rate trends.
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 only 50%: 'project' and 'period' are documented in the schema, but 'stat' (received/rejected/blacklisted) and 'interval' (1h/1d) have enums with no explanation. The description's phrase 'over a time range' loosely gestures at 'period' but adds no meaning for the undocumented enum parameters.
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 states a specific verb and resource ('Get error rate trends for a Sentry project') and adds a scoping dimension ('over a time range'). It is clearly distinguishable from sibling readers like sentry_list_issues or sentry_get_issue, but it never names those siblings or otherwise differentiates itself explicitly.
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 guidance on when to use this tool versus alternatives such as sentry_search_by_trace, sentry_get_issue_events, or the OpenMeter usage tools. No prerequisites, exclusions, or routing conditions are given; usage is only implied by the name and description.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.