Agent Preflight
Budgeted agent preflight: allow|block|reuse|defer|advise. Never executes destination tools. Free MCP
我該用這個嗎
品質與安全性
A
發現項目（2）
- HIGHTool poisoning patterns detected
- MEDIUMTool description contains URL to non-standard domain在 preflight_tool_call 中
根據工具定義與協定合規性的自動化分析。
上下文成本
~1,698Token（工具定義）
~9.0 KB典型回應大小
中等的注意力影響（128k 上下文的 1.33%）
這是每次將伺服器的工具載入模型上下文時所消耗的約略 token 數量。數量越高，可用於其他工作的注意力就越少。
安裝
一鍵安裝
將以下內容加入你的 `claude_desktop_config.json` 檔案：
{
"mcpServers": {
"agent-preflight": {
"url": "https://api.agent-preflight.com/mcp"
}
}
}遠端端點
https://api.agent-preflight.com/mcpstreamable-http它能做什麼
工具清單
工具（2）
🟢 唯讀🟡 寫入🔴 刪除⚪ 未知
🟢check_request(request, schema, economics)
Validate an HTTP API request body against a supplied JSON Schema before sending it. This tool does not execute the request. Use it when an agent needs to determine whether a proposed JSON body satisfies its expected schema. Optional economics adds proceed/abort advice from expected waste versus a $0.001 check.
輸入結構描述
{
"type": "object",
"properties": {
"request": {
"type": "object",
"properties": {
"method": {
"type": "string",
"description": "HTTP method of the proposed request"
},
"url": {
"type": "string",
"description": "Absolute http(s) URL. This tool never fetches the URL."
},
"headers": {
"description": "HTTP headers as string key/value pairs",
"type": "object",
"propertyNames": {
"type": "string"
},
"additionalProperties": {
"type": "string"
}
},
"query": {
"description": "Query parameters",
"type": "object",
"propertyNames": {
"type": "string"
},
"additionalProperties": {}
},
"body": {
"description": "JSON body checked against schema"
}
},
"required": [
"method",
"url"
]
},
"schema": {
"type": "object",
"propertyNames": {
"type": "string"
},
"additionalProperties": {},
"description": "JSON Schema applied to request.body"
},
"economics": {
"description": "Optional V0.2 cost context. Omit for V0.1 validation-only output.",
"type": "object",
"properties": {
"downstreamCostUsd": {
"type": "number",
"minimum": 0,
"description": "USD cost of the target API attempt or success"
},
"billsOnInvalidRequest": {
"type": "boolean",
"description": "True when the target API charges or consumes quota on 4xx"
},
"retryCostUsd": {
"type": "number",
"minimum": 0,
"description": "USD model/tool-turn cost of one failed attempt"
},
"priorInvalidProbability": {
"description": "Prior probability the payload is doomed. Default 0.25",
"type": "number",
"minimum": 0,
"maximum": 1
},
"preflightPriceUsd": {
"description": "Price of this check. Default 0.001",
"type": "number",
"minimum": 0
},
"budgetRemainingUsd": {
"description": "Remaining agent budget. Checks above this are not +EV",
"type": "number",
"minimum": 0
}
},
"required": [
"downstreamCostUsd",
"billsOnInvalidRequest",
"retryCostUsd"
]
}
},
"required": [
"request",
"schema"
],
"$schema": "https://json-schema.org/draft/2020-12/schema"
}輸出結構描述
{
"type": "object",
"properties": {
"valid": {
"type": "boolean"
},
"errors": {
"type": "array",
"items": {
"type": "object",
"properties": {
"path": {
"type": "string"
},
"code": {
"type": "string"
},
"message": {
"type": "string"
}
},
"required": [
"path",
"code",
"message"
],
"additionalProperties": false
}
},
"warnings": {
"type": "array",
"items": {
"type": "object",
"properties": {
"path": {
"type": "string"
},
"code": {
"type": "string"
},
"message": {
"type": "string"
}
},
"required": [
"path",
"code",
"message"
],
"additionalProperties": false
}
},
"requestHash": {
"type": "string"
},
"economics": {
"type": "object",
"properties": {
"decision": {
"type": "string",
"enum": [
"proceed",
"abort"
]
},
"reason": {
"type": "string",
"enum": [
"valid",
"invalid_doomed_request"
]
},
"preflightPriceUsd": {
"type": "number"
},
"wasteIfSentUsd": {
"type": "number"
},
"realizedNetUsd": {
"type": "number"
},
"worthCheckingAPriori": {
"type": "boolean"
},
"aPrioriExpectedWasteUsd": {
"type": "number"
},
"aPrioriExpectedNetUsd": {
"type": "number"
}
},
"required": [
"decision",
"reason",
"preflightPriceUsd",
"wasteIfSentUsd",
"realizedNetUsd",
"worthCheckingAPriori",
"aPrioriExpectedWasteUsd",
"aPrioriExpectedNetUsd"
],
"additionalProperties": false
}
},
"required": [
"valid",
"errors",
"warnings",
"requestHash"
],
"$schema": "https://json-schema.org/draft/2020-12/schema",
"additionalProperties": false
}🟢preflight_tool_call(runId, stepId, tool, budget, task, ...)
Free MCP decision for generic search:web_search or browse:fetch proposals only. Returns structuredContent and JSON text, never destination results. Caller supplies cost estimates, post-consultation budget and history, executes tools and retrieves resultReference itself. Reuse requires explicit permission, positive TTL and matching nonempty goal hashes; history must belong to the caller. estimated fees/savings are hypothetical, not receipts; confidence is not calibrated. Paid HTTP is a separate $0.001 per settled POST interface. Full contract: https://agent-preflight.com/docs
輸入結構描述
{
"type": "object",
"properties": {
"runId": {
"type": "string"
},
"stepId": {
"type": "string"
},
"tool": {
"type": "object",
"properties": {
"provider": {
"type": "string"
},
"operation": {
"type": "string"
},
"request": {
"type": "object",
"propertyNames": {
"type": "string"
},
"additionalProperties": {}
},
"estimatedExternalCostUsd": {
"type": "number",
"minimum": 0
},
"estimatedModelCostUsd": {
"type": "number",
"minimum": 0
}
},
"required": [
"provider",
"operation",
"request",
"estimatedExternalCostUsd"
]
},
"budget": {
"type": "object",
"properties": {
"remainingUsd": {
"type": "number",
"minimum": 0
},
"reservedUsd": {
"type": "number",
"minimum": 0
},
"maxToolCallsRemaining": {
"type": "integer",
"minimum": 0,
"maximum": 9007199254740991
}
},
"required": [
"remainingUsd"
]
},
"task": {
"type": "object",
"properties": {
"goalHash": {
"type": "string"
}
},
"required": [
"goalHash"
]
},
"history": {
"type": "array",
"items": {
"type": "object",
"properties": {
"toolCallId": {
"type": "string"
},
"fingerprint": {
"type": "string"
},
"outcome": {
"type": "string",
"enum": [
"success",
"terminal_failure",
"transient_failure"
]
},
"resultReference": {
"type": "string"
},
"ageSeconds": {
"type": "number",
"minimum": 0
},
"goalHash": {
"type": "string"
}
},
"required": [
"toolCallId",
"fingerprint",
"outcome",
"ageSeconds"
]
}
},
"capabilities": {
"type": "object",
"properties": {
"canReusePriorResult": {
"type": "boolean"
},
"canReduceScope": {
"type": "boolean"
}
}
},
"freshnessTtlSeconds": {
"type": "number",
"minimum": 0
},
"retryCap": {
"type": "integer",
"minimum": 1,
"maximum": 9007199254740991
},
"preflightPriceUsd": {
"type": "number",
"minimum": 0
}
},
"required": [
"runId",
"stepId",
"tool",
"budget"
],
"$schema": "https://json-schema.org/draft/2020-12/schema"
}輸出結構描述
{
"type": "object",
"properties": {
"decision": {
"type": "string",
"enum": [
"allow",
"block",
"reuse",
"defer",
"advise"
]
},
"enforcement": {
"type": "string",
"enum": [
"execute",
"safe_to_skip",
"advisory"
]
},
"reasonCodes": {
"type": "array",
"items": {
"type": "string"
}
},
"issues": {
"type": "array",
"items": {
"type": "object",
"properties": {
"path": {
"type": "string"
},
"code": {
"type": "string"
},
"message": {
"type": "string"
}
},
"required": [
"path",
"code",
"message"
],
"additionalProperties": false
}
},
"requestFingerprint": {
"description": "SHA-256 of version-2 exact proposal; absent on invalid input",
"type": "string"
},
"matchedCallId": {
"type": "string"
},
"estimated": {
"type": "object",
"properties": {
"preflightCostUsd": {
"type": "number"
},
"priceChargedUsd": {
"type": "number",
"description": "Modeled fee, not a settlement receipt"
},
"avoidableExternalCostUsd": {
"type": "number"
},
"avoidableModelCostUsd": {
"type": "number"
},
"netSavingsUsd": {
"type": "number"
},
"billable": {
"type": "boolean",
"description": "Modeled actionable status; MCP is unpaid"
},
"confidence": {
"type": "number",
"description": "Rule constant, not a calibrated probability"
}
},
"required": [
"preflightCostUsd",
"priceChargedUsd",
"avoidableExternalCostUsd",
"avoidableModelCostUsd",
"netSavingsUsd",
"billable",
"confidence"
],
"additionalProperties": false
},
"recommendation": {
"type": "object",
"properties": {
"action": {
"type": "string"
},
"resultReference": {
"type": "string"
}
},
"required": [
"action"
],
"additionalProperties": false
}
},
"required": [
"decision",
"enforcement",
"reasonCodes",
"issues"
],
"$schema": "https://json-schema.org/draft/2020-12/schema",
"additionalProperties": false
}社群
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已驗證未記錄版本2 個工具
已驗證未記錄版本2 個工具