mcp-vdd

Detect Environment

vdd_detect_environment

Read-onlyIdempotent

Detect required vs optional tools/MCPs for each VDD phase and helpers, compare against available host agent tools, and return a read-only capability report to plan dispatch or diagnose missing tools.

Instructions

VDD Environment Detection: Report which tools/MCPs each VDD phase requires vs treats as optional — across the 8-phase pipeline (init through validate) plus the cross-phase helpers (amend, clone, inspect, get-next-task) — and which of the host agent availableTools are present vs missing. Read-only; returns a capability report without modifying files. Run before vdd_strategize to plan research-subagent dispatch, or when a phase fails for lack of a tool; to inspect artifacts instead of capabilities use vdd_inspect. Returns a fixed-shape capability report; tool-name matching is normalized, so pass names as your host exposes them. Parameter relationships: availableTools and capabilities are aliases; omit both to get the per-phase requirements without a present/missing comparison.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`projectRoot`	No	Project root: directory that constitution.md and the vdd/ folder are written to and resolved against. Relative paths resolve from the current working directory; keep the same value across every phase (default ".")	.
`capabilities`	No	Alias for availableTools
`availableTools`	No	MCP/tool names available to the host agent (e.g., ["brave-search","perplexity","context7","gh_grep","playwright","filesystem"])

Output Schema

TableJSON Schema

Name	Required	Description
`_sdt`	Yes	Strategy-and-Tactic instructions for the next step
`error`	No	Error message when the phase fails
`_phase`	Yes	VDD phase that produced this result
`output`	No	Additional structured phase output
`success`	Yes	Whether the phase completed successfully
`artifact`	No	Primary artifact produced or returned
`gateResult`	No	Quality-gate result, when the phase runs a gate

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedv1.9.0Oct 2, 2026

changedInput schema / properties / projectRoot / description

Previous value: -"Project root: directory that constitution.md and the vdd/ folder are written to and resolved against (default \".\")"New value: +"Project root: directory that constitution.md and the vdd/ folder are written to and resolved against. Relative paths resolve from the current working directory; keep the same value across every phase (default \".\")"

Changed1 schema field changedv0.1.3Sep 24, 2026

changedInput schema / properties / projectRoot / description

Previous value: -"Path to project root directory"New value: +"Project root: directory that constitution.md and the vdd/ folder are written to and resolved against (default \".\")"

Changed1 schema field changedv0.1.2Sep 24, 2026

changedOutput schema / (root)

Previous value: -nullNew value: +{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "additionalProperties": false,
+  "properties": {
+    "_phase": {
+      "description": "VDD phase that produced this result",
+      "type": "string"
+    },
+    "_sdt": {
+      "description": "Strategy-and-Tactic instructions for the next step",
+      "type": "string"
+    },
+    "artifact": {
+      "description": "Primary artifact produced or returned",
+      "type": "string"
+    },
+    "error": {
+      "description": "Error message when the phase fails",
+      "type": "string"
+    },
+    "gateResult": {
+      "additionalProperties": false,
+      "description": "Quality-gate result, when the phase runs a gate",
+      "properties": {
+        "checks": {
+          "description": "Number of checks run",
+          "type": "number"
+        },
+        "passed": {
+          "description": "Whether the quality gate passed",
+          "type": "boolean"
+        },
+        "total": {
+          "description": "Total number of checks",
+          "type": "number"
+        }
+      },
+      "required": [
+        "passed",
+        "checks",
+        "total"
+      ],
+      "type": "object"
+    },
+    "output": {
+      "additionalProperties": {},
+      "description": "Additional structured phase output",
+      "propertyNames": {
+        "type": "string"
+      },
+      "type": "object"
+    },
+    "success": {
+      "description": "Whether the phase completed successfully",
+      "type": "boolean"
+    }
+  },
+  "required": [
+    "success",
+    "_phase",
+    "_sdt"
+  ],
+  "type": "object"
+}

First observedv0.1.0Sep 24, 2026

TDQS

A4.6/5.0

Behavior4/5

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

Annotations already declare readOnlyHint/idempotentHint/openWorldHint=false, so the safety profile is covered; the description reinforces 'Read-only; returns a capability report without modifying files' and adds genuinely new behavioral detail in the normalized tool-name matching and the fixed-shape report. It stops short of describing response structure beyond that, so it lands just below the top.

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?

Front-loaded with purpose and every clause carries information (scope, phases, read-only, alternatives, aliases, normalization). It is dense and slightly run-on as a single paragraph, but nothing is filler; a small trim would make it ideal.

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

Completeness5/5

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

With an output schema present the description need not explain return values, and it still covers purpose, usage, aliasing, and parameter relationships. Nothing an agent needs in order to call this correctly is missing.

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

Parameters4/5

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

Schema coverage is 100% (baseline 3), but the description adds real value beyond the schema by stating that availableTools and capabilities are aliases and that omitting both yields per-phase requirements without a present/missing comparison. It also clarifies how to pass tool names given normalization.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

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

States a specific verb+resource (report required vs optional tools per VDD phase and present vs missing host tools) and scopes it precisely across the 8-phase pipeline plus cross-phase helpers. It explicitly distinguishes itself from the sibling vdd_inspect, so an agent can route without opening either schema.

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

Usage Guidelines5/5

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

Gives explicit trigger conditions (before vdd_strategize, or when a phase fails for lack of a tool) and names the alternative to use instead (vdd_inspect for artifacts rather than capabilities). This is exactly the when/when-not/alternative shape that earns a top score.

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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