Heista's creative direction engine — same engine the Creative Director specialist runs internally, exposed over MCP. ONE-SHOT: give a brief, get N finished creative outputs. For back-and-forth refinement, or output shapes the medium enum below does not cover, use chat_with_creative_worlds instead...
Part of the Heista server.
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AI agents use call_creative_worlds to create or modify resources in Heista. 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 call_creative_worlds 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 Heista.
Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.
{
"version": "1",
"default": "deny",
"tools": {
"call_creative_worlds": {
"limits": [
{
"counter": "call_creative_worlds_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}See the full Heista policy for all 69 tools.
These attack patterns abuse exactly the kind of access call_creative_worlds 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.
Heista's creative direction engine — same engine the Creative Director specialist runs internally, exposed over MCP. ONE-SHOT: give a brief, get N finished creative outputs. For back-and-forth refinement, or output shapes the medium enum below does not cover, use chat_with_creative_worlds instead. OUTPUT SHAPE switches on the medium arg: • omitted → N territory cards (default exploration). Each card sits on different psychology / craft / feel / world axis coordinates so the set spans the creative space rather than orbiting one insight. Card has: name, campaign line, 5-8 sentence pitch, one-sentence strategic bet, resolved axis state names, creative-director rationale. • tvc → N TVC scripts (15-90s — hook, arc, resolve, sound design, end line). • billboard / ooh / print → N out-of-home concepts (visual concept + line + placement rationale). • social → N social-video concepts (hook + format type + middle beat + payoff, optimised for Reels / TikTok / Shorts). • activation / experiential → N activation concepts (space design + user journey + peak moment + takeaway artifact). • audio → N sonic / radio concepts (sonic scene + voice + audio arc). • campaign → N full campaign platforms (insight → big idea → strategy → visual world → production roadmap). The engine can also produce manifesto / copy, naming, packaging, PR stunts, content series, brand positioning, partnerships — these output shapes are NOT in the medium enum, so use chat_with_creative_worlds when the user wants one of those. USE WHEN: user says "give me ideas / options / directions / territories", "what angles work for...", "show me three / five ways to...", "write a TVC for...", "draft billboard concepts for...", "I need fresh thinking on...". DO NOT USE to refine one existing direction (use chat tool), to critique work, for OKRs / internal docs / strategy decks, or anything outside advertising creative direction. INPUTS: brief (the creative problem, free text), count (2-6 concepts), optional brand_id (from list_brands or any create_powersource_* — when provided the engine grounds output in the brand's buyer tensions, voice, and selling points), optional medium (above), optional lens_hint (apply a playbook or signature move as a creative constraint), idempotency_key (safely retryable for 5 minutes). Returns the finished creative output as narrative text PLUS a structured array of resolved axis coordinates for programmatic use. Metered — typically 3-15 credits per call depending on count and brand context size. Charged after success on actual token usage.. It is categorised as a Write tool in the Heista MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Heista MCP server in PolicyLayer and add a rule for call_creative_worlds: 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 Heista. Nothing to install.
call_creative_worlds 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 call_creative_worlds 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 call_creative_worlds. 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.
call_creative_worlds is provided by the Heista MCP server (https://www.heista.co/api/mcp/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 69 Heista tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
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