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compare_profiles

Idempotent

Compare two stored analyses to detect meaningful performance profile differences and store bounded evidence for review.

Instructions

Compare two stored analyses and store bounded profile-difference evidence.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`baseline_analysis_id`	Yes
`candidate_analysis_id`	Yes
`minimum_delta_percent`	No

Output Schema

TableJSON Schema

Name	Required	Default
`uri`	Yes
`summary`	Yes
`artifact_id`	Yes
`artifact_type`	Yes
`schema_version`	No	1.0
`evidence_quality`	No

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"
+}

Changed2 schema fields changedv0.3.0Aug 21, 2026

addedOutput schema / $defs

Added value: +{
+  "EvidenceQuality": {
+    "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 / properties / evidence_quality

Added value: +{
+  "anyOf": [
+    {
+      "$ref": "#/$defs/EvidenceQuality"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null
+}

First observedv0.1.0Aug 1, 2026

TDQS

C2.9/5.0

Behavior3/5

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

Annotations already convey readOnlyHint=false, idempotentHint=true, and destructiveHint=false. The description adds that the tool stores evidence, which is a useful non-obvious side effect, but it does not explain what 'bounded profile-difference evidence' means or what exactly gets persisted.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single front-loaded sentence with no redundancy. However, the phrase 'bounded profile-difference evidence' is vague jargon that could have been simplified, so it is concise but not maximally clear.

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?

Given there is an output schema, returning values need not be explained, but the description still leaves significant gaps: parameter semantics (especially minimum_delta_percent), how 'evidence' is stored, and when this tool should be selected over sibling compare tools. This is under-specified for safe invocation.

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%, so the description must compensate. It only implies baseline_analysis_id and candidate_analysis_id refer to the two stored analyses, but it does not clarify their roles or explain minimum_delta_percent at all, leaving an optional threshold parameter undocumented.

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 states a clear verb ('Compare') and resource ('two stored analyses'), and adds that it stores 'bounded profile-difference evidence,' which distinguishes it from pure comparison tools. It does not explicitly name sibling tools, so it narrowly misses a 5.

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

Usage Guidelines2/5

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

No guidance is given about when to use compare_profiles versus alternatives like compare_benchmarks, compare_container_measurements, or compare_docker_optimization_iterations. The agent must infer the intended context from the tool name and vague phrase 'stored analyses.'

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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