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list_hotspots

Read-onlyIdempotent

Fetch paginated hotspots from a stored performance analysis, with sorting and category filters, to identify and pinpoint bottlenecks.

Instructions

Return a bounded page of hotspots from a stored analysis.

Input Schema

TableJSON Schema

Name	Required	Default
`limit`	No
`cursor`	No
`sort_by`	No	self_percent
`category`	No
`analysis_id`	Yes

Output Schema

TableJSON Schema

Name	Required	Default
`items`	Yes
`analysis_id`	Yes
`next_cursor`	No
`total_items`	Yes
`schema_version`	No	1.0
`evidence_quality`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Changed12 schema fields changedv0.3.2Aug 28, 2026

addedOutput schema / $defs / EvidenceQuality / properties / kernel_context_self_percent

Added value: +{
+  "anyOf": [
+    {
+      "maximum": 100,
+      "minimum": 0,
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "title": "Kernel Context Self Percent"
+}

addedOutput schema / $defs / EvidenceQuality / properties / kernel_context_self_weight

Added value: +{
+  "anyOf": [
+    {
+      "minimum": 0,
+      "type": "integer"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "title": "Kernel Context Self Weight"
+}

addedOutput schema / $defs / EvidenceQuality / properties / unknown_context_self_percent

Added value: +{
+  "anyOf": [
+    {
+      "maximum": 100,
+      "minimum": 0,
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "title": "Unknown Context Self Percent"
+}

addedOutput schema / $defs / EvidenceQuality / properties / unknown_context_self_weight

Added value: +{
+  "anyOf": [
+    {
+      "minimum": 0,
+      "type": "integer"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "title": "Unknown Context Self Weight"
+}

addedOutput schema / $defs / EvidenceQuality / properties / unresolved_kernel_self_percent

Added value: +{
+  "anyOf": [
+    {
+      "maximum": 100,
+      "minimum": 0,
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "title": "Unresolved Kernel Self Percent"
+}

addedOutput schema / $defs / EvidenceQuality / properties / unresolved_kernel_self_weight

Added value: +{
+  "anyOf": [
+    {
+      "minimum": 0,
+      "type": "integer"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "title": "Unresolved Kernel Self Weight"
+}

addedOutput schema / $defs / EvidenceQuality / properties / unresolved_unknown_context_self_percent

Added value: +{
+  "anyOf": [
+    {
+      "maximum": 100,
+      "minimum": 0,
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "title": "Unresolved Unknown Context Self Percent"
+}

addedOutput schema / $defs / EvidenceQuality / properties / unresolved_unknown_context_self_weight

Added value: +{
+  "anyOf": [
+    {
+      "minimum": 0,
+      "type": "integer"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "title": "Unresolved Unknown Context Self Weight"
+}

addedOutput schema / $defs / EvidenceQuality / properties / unresolved_user_self_percent

Added value: +{
+  "anyOf": [
+    {
+      "maximum": 100,
+      "minimum": 0,
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "title": "Unresolved User Self Percent"
+}

addedOutput schema / $defs / EvidenceQuality / properties / unresolved_user_self_weight

Added value: +{
+  "anyOf": [
+    {
+      "minimum": 0,
+      "type": "integer"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "title": "Unresolved User Self Weight"
+}

addedOutput schema / $defs / EvidenceQuality / properties / user_context_self_percent

Added value: +{
+  "anyOf": [
+    {
+      "maximum": 100,
+      "minimum": 0,
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "title": "User Context Self Percent"
+}

addedOutput schema / $defs / EvidenceQuality / properties / user_context_self_weight

Added value: +{
+  "anyOf": [
+    {
+      "minimum": 0,
+      "type": "integer"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "title": "User Context Self Weight"
+}

Changed9 schema fields changedv0.3.0Aug 21, 2026

addedOutput schema / $defs / EvidenceQuality

Added value: +{
+  "additionalProperties": false,
+  "properties": {
+    "actual_event_source": {
+      "default": "unknown",
+      "enum": [
+        "hardware",
+        "software",
+        "unknown"
+      ],
+      "title": "Actual Event Source",
+      "type": "string"
+    },
+    "address_annotation_line_count": {
+      "minimum": 0,
+      "title": "Address Annotation Line Count",
+      "type": "integer"
+    },
+    "aggregated_frame_occurrence_count": {
+      "minimum": 0,
+      "title": "Aggregated Frame Occurrence Count",
+      "type": "integer"
+    },
+    "allowed_conclusions": {
+      "default": [],
+      "items": {
+        "type": "string"
+      },
+      "title": "Allowed Conclusions",
+      "type": "array"
+    },
+    "call_graph_weight": {
+      "minimum": 0,
+      "title": "Call Graph Weight",
+      "type": "integer"
+    },
+    "call_graph_weight_percent": {
+      "maximum": 100,
+      "minimum": 0,
+      "title": "Call Graph Weight Percent",
+      "type": "number"
+    },
+    "collection_limitations": {
+      "default": [],
+      "items": {
+        "type": "string"
+      },
+      "title": "Collection Limitations",
+      "type": "array"
+    },
+    "duplicate_frame_line_count": {
+      "minimum": 0,
+      "title": "Duplicate Frame Line Count",
+      "type": "integer"
+    },
+    "event": {
+      "title": "Event",
+      "type": "string"
+    },
+    "exported_call_path_count": {
+      "minimum": 0,
+      "title": "Exported Call Path Count",
+      "type": "integer"
+    },
+    "exported_hotspot_count": {
+      "minimum": 0,
+      "title": "Exported Hotspot Count",
+      "type": "integer"
+    },
+    "fallback_reason": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "default": null,
+      "title": "Fallback Reason"
+    },
+    "fallback_used": {
+      "anyOf": [
+        {
+          "type": "boolean"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "default": null,
+      "title": "Fallback Used"
+    },
+    "forbidden_conclusions": {
+      "default": [],
+      "items": {
+        "type": "string"
+      },
+      "title": "Forbidden Conclusions",
+      "type": "array"
+    },
+    "frame_line_count": {
+      "minimum": 0,
+      "title": "Frame Line Count",
+      "type": "integer"
+    },
+    "inline_frame_count": {
+      "minimum": 0,
+      "title": "Inline Frame Count",
+      "type": "integer"
+    },
+    "input_bytes": {
+      "minimum": 0,
+      "title": "Input Bytes",
+      "type": "integer"
+    },
+    "input_sha256": {
+      "pattern": "^[a-f0-9]{64}$",
+      "title": "Input Sha256",
+      "type": "string"
+    },
+    "limitations": {
+      "default": [],
+      "items": {
+        "type": "string"
+      },
+      "title": "Limitations",
+      "type": "array"
+    },
+    "malformed_record_count": {
+      "minimum": 0,
+      "title": "Malformed Record Count",
+      "type": "integer"
+    },
+    "normalization_merge_count": {
+      "minimum": 0,
+      "title": "Normalization Merge Count",
+      "type": "integer"
+    },
+    "omitted_call_path_weight": {
+      "minimum": 0,
+      "title": "Omitted Call Path Weight",
+      "type": "integer"
+    },
+    "omitted_hotspot_self_weight": {
+      "minimum": 0,
+      "title": "Omitted Hotspot Self Weight",
+      "type": "integer"
+    },
+    "parser_invariants_passed": {
+      "title": "Parser Invariants Passed",
+      "type": "boolean"
+    },
+    "quality_status": {
+      "enum": [
+        "verified",
+        "partial"
+      ],
+      "title": "Quality Status",
+      "type": "string"
+    },
+    "sample_count": {
+      "minimum": 0,
+      "title": "Sample Count",
+      "type": "integer"
+    },
+    "schema_version": {
+      "const": "1.0",
+      "default": "1.0",
+      "title": "Schema Version",
+      "type": "string"
+    },
+    "source_annotation_line_count": {
+      "minimum": 0,
+      "title": "Source Annotation Line Count",
+      "type": "integer"
+    },
+    "source_collection_artifact_sha256": {
+      "anyOf": [
+        {
+          "pattern": "^[a-f0-9]{64}$",
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "default": null,
+      "title": "Source Collection Artifact Sha256"
+    },
+    "source_collection_id": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "default": null,
+      "title": "Source Collection Id"
+    },
+    "source_line_frame_count": {
+      "minimum": 0,
+      "title": "Source Line Frame Count",
+      "type": "integer"
+    },
+    "source_line_self_percent": {
+      "maximum": 100,
+      "minimum": 0,
+      "title": "Source Line Self Percent",
+      "type": "number"
+    },
+    "source_line_self_weight": {
+      "minimum": 0,
+      "title": "Source Line Self Weight",
+      "type": "integer"
+    },
+    "source_locations_truncated_hotspot_count": {
+      "minimum": 0,
+      "title": "Source Locations Truncated Hotspot Count",
+      "type": "integer"
+    },
+    "total_call_path_count": {
+      "minimum": 0,
+      "title": "Total Call Path Count",
+      "type": "integer"
+    },
+    "total_hotspot_count": {
+      "minimum": 0,
+      "title": "Total Hotspot Count",
+      "type": "integer"
+    },
+    "total_weight": {
+      "minimum": 0,
+      "title": "Total Weight",
+      "type": "integer"
+    },
+    "unicode_replacement_count": {
+      "minimum": 0,
+      "title": "Unicode Replacement Count",
+      "type": "integer"
+    },
+    "unresolved_self_percent": {
+      "maximum": 100,
+      "minimum": 0,
+      "title": "Unresolved Self Percent",
+      "type": "number"
+    },
+    "unresolved_self_weight": {
+      "minimum": 0,
+      "title": "Unresolved Self Weight",
+      "type": "integer"
+    },
+    "warning_count": {
+      "minimum": 0,
+      "title": "Warning Count",
+      "type": "integer"
+    },
+    "warnings_truncated": {
+      "title": "Warnings Truncated",
+      "type": "boolean"
+    },
+    "weight_source": {
+      "title": "Weight Source",
+      "type": "string"
+    },
+    "weight_unit": {
+      "title": "Weight Unit",
+      "type": "string"
+    }
+  },
+  "required": [
+    "quality_status",
+    "parser_invariants_passed",
+    "input_sha256",
+    "input_bytes",
+    "sample_count",
+    "total_weight",
+    "event",
+    "weight_unit",
+    "weight_source",
+    "malformed_record_count",
+    "warning_count",
+    "warnings_truncated",
+    "unicode_replacement_count",
+    "frame_line_count",
+    "duplicate_frame_line_count",
+    "address_annotation_line_count",
+    "source_annotation_line_count",
+    "aggregated_frame_occurrence_count",
+    "unresolved_self_weight",
+    "unresolved_self_percent",
+    "call_graph_weight",
+    "call_graph_weight_percent",
+    "source_line_frame_count",
+    "source_line_self_weight",
+    "source_line_self_percent",
+    "inline_frame_count",
+    "normalization_merge_count",
+    "source_locations_truncated_hotspot_count",
+    "total_hotspot_count",
+    "exported_hotspot_count",
+    "omitted_hotspot_self_weight",
+    "total_call_path_count",
+    "exported_call_path_count",
+    "omitted_call_path_weight"
+  ],
+  "title": "EvidenceQuality",
+  "type": "object"
+}

addedOutput schema / $defs / Hotspot / properties / normalization_merged

Added value: +{
+  "default": false,
+  "title": "Normalization Merged",
+  "type": "boolean"
+}

addedOutput schema / $defs / Hotspot / properties / source_locations_truncated

Added value: +{
+  "default": false,
+  "title": "Source Locations Truncated",
+  "type": "boolean"
+}

addedOutput schema / $defs / Hotspot / properties / symbol_variant_count

Added value: +{
+  "description": "Exact raw-symbol variant count when symbol_variants_truncated is false; otherwise a conservative observed lower bound",
+  "minimum": 0,
+  "title": "Symbol Variant Count",
+  "type": "integer"
+}

addedOutput schema / $defs / Hotspot / properties / symbol_variants

Added value: +{
+  "default": [],
+  "items": {
+    "type": "string"
+  },
+  "title": "Symbol Variants",
+  "type": "array"
+}

addedOutput schema / $defs / Hotspot / properties / symbol_variants_truncated

Added value: +{
+  "default": false,
+  "title": "Symbol Variants Truncated",
+  "type": "boolean"
+}

changedOutput schema / $defs / Hotspot / required

Previous value: -[
-  "hotspot_id",
-  "symbol",
-  "dso",
-  "self_weight",
-  "inclusive_weight",
-  "sample_count",
-  "stack_occurrence_count",
-  "self_percent",
-  "inclusive_percent",
-  "thread_count"
-]New value: +[
+  "hotspot_id",
+  "symbol",
+  "dso",
+  "self_weight",
+  "inclusive_weight",
+  "sample_count",
+  "stack_occurrence_count",
+  "self_percent",
+  "inclusive_percent",
+  "thread_count",
+  "symbol_variant_count"
+]

addedOutput schema / properties / evidence_quality

Added value: +{
+  "$ref": "#/$defs/EvidenceQuality"
+}

changedOutput schema / required

Previous value: -[
-  "analysis_id",
-  "items",
-  "total_items"
-]New value: +[
+  "analysis_id",
+  "evidence_quality",
+  "items",
+  "total_items"
+]

First observedv0.1.0Aug 1, 2026

TDQS

B3.2/5.0

Behavior3/5

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

Annotations already disclose readOnly, idempotent, non-destructive behavior, so the description does not need to repeat those traits. It adds the useful 'bounded page' behavioral detail but says nothing about sort_defaults, filter behavior, cursor semantics, or what happens when the page is exhausted. This is acceptable but not rich.

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 a single concise sentence with no redundant filler. The core action and resource are front-loaded, and every word contributes meaning.

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

Completeness2/5

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

Despite a strong annotation set and output schema, the tool has five parameters involving pagination, filtering, and sorting, and the description does not explain any of them. It also lacks usage guidance relative to sibling tools, leaving the agent to infer important selection and invocation details.

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

Parameters2/5

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

Schema description coverage is 0%, and the description does not explain limit, cursor, sort_by, category, or analysis_id beyond implying pagination via 'bounded page'. The schema provides defaults and an enum, but the description adds no meaning for the filter and sorting parameters, so it 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.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly names a specific verb ('Return') and resource ('a bounded page of hotspots from a stored analysis'), and the 'bounded page' wording signals pagination rather than detail retrieval. It does not explicitly contrast with sibling tools such as get_hotspot_details or classify_hotspots, so it falls just short of full sibling differentiation.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The phrase 'from a stored analysis' implies the tool should be used after an analysis has been saved, but there is no explicit when-to-use guidance, prerequisite mention, or direction to alternatives like get_hotspot_details for a single hotspot. Usage context is only implied, not stated.

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

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