Ambr
by getambr · remote · no sign-in to list tools · v0.3.0 · published by GitHub user getambr
Ricardian contracts for AI agents — dual-format, SHA-256 bound, legible by construction.
6 tools: 3 change things and 3 only read.
Scanned Oct 21, 2026
- Deletes or cancels0Claude Code: deny
- Can't be undone0Claude Code: ask
- Changes things3Claude Code: ask: see these tools
- Only reads3Claude Code: allow: see these tools
No check matched anything in the tool definitions. No finding is not a safety guarantee. How the checks work.
claude mcp add --transport http ambr https://getamber.dev/api/mcpTools
Open a tool for its reasons and full description. Descriptions are the publisher's own words, shown as they are.
6 tools
Changes things 3Claude Code: ask
ambr_agent_handshakeInitiate a handshake on a contract on behalf of your delegating principal.No findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
Description, as the server wrote it Initiate a handshake on a contract on behalf of your delegating principal. Requires an API key with an active delegation (principal wallet registered via /api/v1/delegations). Records the agent's intent to accept, reject, or request changes on the contract. The principal must separately approve via wallet signature on the Reader Portal. Args: - contract_id (string, required): Contract ID (amb-YYYY-NNNN), SHA-256 hash, or UUID - intent (string, required): "accept" | "reject" | "request_changes" - message (string, optional): Note for the counterparty - visibility_preference (string, optional): "private" | "metadata_only" | "public" | "encrypted" Returns: Handshake status and next steps for principal approval. Legibility: the handshake itself is auditable — delegation scope, agent identity, and principal approval are recorded alongside the contract hash.
Annotations the server declares
- readOnlyHint: false
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false
ambr_create_contractGenerate a Ricardian Contract from a template.No findings
Why it is in this group
- The name "ambr_create_contract" says "create": a word for a change.
Description, as the server wrote it Generate a Ricardian Contract from a template. Creates a dual-format contract (human-readable legal text + machine-parsable JSON) using AI, linked by SHA-256 hash. The contract is stored on Ambr and accessible via the Reader Portal. Requires a valid API key (X-API-Key header on the HTTP request) with available credits. Use ambr_list_templates first to discover templates and their required parameters. Args: - template (string, required): Template slug (e.g. "d1-general-auth") - parameters (object, required): Template-specific parameters matching the schema - principal_declaration (object, required): { agent_id, principal_name, principal_type } - parent_contract_hash (string, optional): SHA-256 hash of parent contract for amendments - oversight_threshold_usd (number, optional): spending level above which work created under this contract needs human approval. Children exceeding it halt at awaiting_principal_approval. - amendment_type (string, optional): "original" | "amendment" | "extension" Returns: - contract_id: Unique ID (e.g. "amb-2026-0042") - sha256_hash: SHA-256 hash for verification - status: Contract status - reader_url: URL to view in Reader Portal - credits_remaining: Remaining API credits Legibility: Output is dual-format by construction and replayable to the original SHA-256 hash — the basis of Ambr's legibility guarantee.
Annotations the server declares
- readOnlyHint: false
- destructiveHint: false
- idempotentHint: false
- openWorldHint: false
ambr_verify_hashVerify a contract's SHA-256 hash to confirm document integrity.No findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Description, as the server wrote it Verify a contract's SHA-256 hash to confirm document integrity. Checks whether the provided hash matches a contract stored on Ambr. Returns verification status, contract metadata, and Reader Portal URL if found. Args: - hash (string, required): SHA-256 hash (64-character hex string) Returns: - verified: boolean - contract_id: string (if found) - status: string (if found) - reader_url: string (if found) Legibility: verification is the point at which legibility becomes provable — matching hash means the prose a human reads and the JSON a machine parses are the same document that was originally signed.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false
Only reads 3Claude Code: allow
ambr_get_contractRetrieve a contract by ID, SHA-256 hash, or UUID.No findings
Why it is in this group
- The name "ambr_get_contract" says "get": a word for reading.
Description, as the server wrote it Retrieve a contract by ID, SHA-256 hash, or UUID. With a valid API key (contract creator): returns the full contract including human-readable text, machine-readable JSON, status, and principal declaration. Without authentication: returns metadata only (contract_id, status, hash, dates). Supports three lookup formats: - Contract ID: "amb-2026-0042" - SHA-256 hash: 64-character hex string - UUID: Standard UUID format Args: - id (string, required): Contract ID, SHA-256 hash, or UUID Returns: Full contract (if authorized) or metadata-only response. Legibility: retrieval preserves the dual-format pairing — prose and JSON always replay to the same SHA-256.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false
ambr_get_contract_statusCheck the status of a contract and its amendment chain.No findings
Why it is in this group
- The name "ambr_get_contract_status" says "get": a word for reading.
Description, as the server wrote it Check the status of a contract and its amendment chain. Returns the current status and any linked amendments (parent or child contracts). Useful for verifying if a contract is active, amended, or terminated. Args: - id (string, required): Contract ID, SHA-256 hash, or UUID Returns: - contract_id, status, created_at - amendment_type, parent_contract_hash - amendments: Array of child contracts (if any) Legibility: amendments are bilateral and themselves dual-format — the chain stays legible from original through every revision.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false
ambr_list_templatesList available contract templates on Ambr.No findings
Why it is in this group
- The name "ambr_list_templates" says "list": a word for reading.
Description, as the server wrote it List available contract templates on Ambr. Returns all active Ricardian Contract templates with their slugs, names, descriptions, categories, parameter schemas, and pricing. Use this to discover which templates are available before creating a contract with ambr_create_contract. No authentication required. Returns: Array of template objects with slug, name, description, category, parameter_schema, price_cents, and version fields. Legibility: templates are the parameter schema for the dual-format contracts you create — starting here keeps your request conformant and your output defensible.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false
This is not a safety rating, and no finding is not a safety guarantee. The groups and findings come from fixed checks of the tool definitions the server returned on the date shown, not from its code or what it does when called. How the checks work.
Install
Pinned to version 0.3.0. Values in angle brackets are yours to fill in.
claude mcp add --transport http ambr https://getamber.dev/api/mcpRun in a terminal.
Claude Code permissions
Allow the reads, ask before a change, deny the deletes. Paste into .claude/settings.json.
{
"permissions": {
"allow": [
"mcp__ambr__ambr_list_templates",
"mcp__ambr__ambr_get_contract",
"mcp__ambr__ambr_get_contract_status"
],
"ask": [
"mcp__ambr__ambr_create_contract",
"mcp__ambr__ambr_verify_hash",
"mcp__ambr__ambr_agent_handshake"
],
"deny": []
}
}Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. It assumes the server is installed as ambr. Review it before you use it.
