Compute an HMAC signature for a message using a secret key. Supports SHA-256 (default), SHA-512, SHA-1, and MD5. Used for API request signing, webhook verification (GitHub, Stripe, Twilio), and JWT validation.
Risk signalsHandles credentials or secrets (secret)
Part of the IA-QA — 130+ QA & Dev Tools for AI Agents server.
Free to start. No card required.
AI agents use generate_hmac to create or modify resources in IA-QA — 130+ QA & Dev Tools for AI Agents. Write operations carry medium risk because an autonomous agent could trigger bulk unintended modifications. Rate limits prevent a single agent session from making hundreds of changes in rapid succession. Argument validation ensures the agent passes expected values.
Without a policy, an AI agent could call generate_hmac repeatedly, creating or modifying resources faster than any human could review. PolicyLayer's rate limiting ensures write operations happen at a controlled pace, and argument validation catches malformed or unexpected inputs before they reach IA-QA — 130+ QA & Dev Tools for AI Agents.
Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.
{
"version": "1",
"default": "deny",
"tools": {
"generate_hmac": {
"limits": [
{
"counter": "generate_hmac_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}See the full IA-QA — 130+ QA & Dev Tools for AI Agents policy for all 146 tools.
These attack patterns abuse exactly the kind of access generate_hmac gives an agent. Each links to the full case and the policy that stops it:
Other write tools across the catalogue. The same approach applies to each: rate-limit and validate the arguments.
Compute an HMAC signature for a message using a secret key. Supports SHA-256 (default), SHA-512, SHA-1, and MD5. Used for API request signing, webhook verification (GitHub, Stripe, Twilio), and JWT validation.. It is categorised as a Write tool in the IA-QA — 130+ QA & Dev Tools for AI Agents MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the IA-QA — 130+ QA & Dev Tools for AI Agents MCP server in PolicyLayer and add a rule for generate_hmac: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches IA-QA — 130+ QA & Dev Tools for AI Agents. Nothing to install.
generate_hmac is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the generate_hmac rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for generate_hmac. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
generate_hmac is provided by the IA-QA — 130+ QA & Dev Tools for AI Agents MCP server (https://www.ia-qa.com/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 146 IA-QA — 130+ QA & Dev Tools for AI Agents tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
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