# When Valid Tool Calls Change Meaning: Formation-Consistent Dispatch for LLM Agents

arXiv: https://arxiv.org/abs/2609.35088 · HTML: https://mlsanity.com/paper/2609.35088/

## Key facts

- No citing papers in the map yet (data through 14 Oct 2026).
- Placed in Software engineering coding agents, one of 16 directions in LLM agents and tool use.
- Builds on 23 of its 65 references that are in the map.
- First posted on arXiv 28 Sep 2026.

## Placed in

- LLM agents and tool use / [Software engineering coding agents](https://mlsanity.com/agents/software-engineering-coding-agents/)

## Builds on (most cited first, 23 of 23)

- [Identifying the Risks of LM Agents with an LM-Emulated Sandbox](https://mlsanity.com/paper/2309.15817/) (2023)
- [InjecAgent: Benchmarking Indirect Prompt Injections in Tool-Integrated Large Language Model Agents](https://mlsanity.com/paper/2403.02691/) (2024)
- [Defeating Prompt Injections by Design](https://mlsanity.com/paper/2503.18813/) (2025)
- [AgentSpec: Customizable Runtime Enforcement for Safe and Reliable LLM Agents](https://mlsanity.com/paper/2503.18666/) (2025)
- [Progent: Securing AI Agents with Privilege Control](https://mlsanity.com/paper/2504.11703/) (2025)
- [IsolateGPT: An Execution Isolation Architecture for LLM-Based Agentic Systems](https://mlsanity.com/paper/2403.04960/) (2024)
- [Contextual Agent Security: A Policy for Every Purpose](https://mlsanity.com/paper/2501.17070/) (2025)
- [ACE: A Security Architecture for LLM-Integrated App Systems](https://mlsanity.com/paper/2504.20984/) (2025)
- [MCPSecBench: A Systematic Security Benchmark and Playground for Testing Model Context Protocols](https://mlsanity.com/paper/2508.13220/) (2025)
- [SAGA: A Security Architecture for Governing AI Agentic Systems](https://mlsanity.com/paper/2504.21034/) (2025)
- [AttriGuard: Defeating Indirect Prompt Injection in LLM Agents via Causal Attribution of Tool Invocations](https://mlsanity.com/paper/2603.10749/) (2026)
- [Cordon: Semantic Transactions for Tool-Using LLM Agents](https://mlsanity.com/paper/2606.17573/) (2026)
- [Towards Automating Data Access Permissions in AI Agents](https://mlsanity.com/paper/2511.17959/) (2025)
- [ETDI: Mitigating Tool Squatting and Rug Pull Attacks in Model Context Protocol (MCP) by using OAuth-Enhanced Tool Definitions and Policy-Based Access Control](https://mlsanity.com/paper/2506.01333/) (2025)
- [Parasites in the Toolchain: A Large-Scale Analysis of Attacks on the MCP Ecosystem](https://mlsanity.com/paper/2509.06572/) (2025)
- [Semantic Attacks on Tool-Augmented LLMs: Securing the Model Context Protocol Against Descriptor-Level Manipulation](https://mlsanity.com/paper/2512.06556/) (2025)
- [ChainCaps: Composition-Safe Tool-Using Agents via Monotonic Capability Attenuation](https://mlsanity.com/paper/2605.26542/) (2026)
- [When AI Meets the Web: Prompt Injection Risks in Third-Party AI Chatbot Plugins](https://mlsanity.com/paper/2511.05797/) (2025)
- [CAVA: Canonical Action Verification and Attestation for Runtime Governance of Agentic AI Systems](https://mlsanity.com/paper/2607.13716/) (2026)
- [It's a Feature, Not a Bug: Secure and Auditable State Rollback for Confidential Cloud Applications](https://mlsanity.com/paper/2511.13641/) (2025)
- [Attested Tool-Server Admission: A Security Extension to the Model Context Protocol](https://mlsanity.com/paper/2605.24248/) (2026)
- [Tool Forge: A Validation-Carrying Toolchain for Governed Agentic Execution](https://mlsanity.com/paper/2605.28000/) (2026)
- [From Tool Connection to Execution Control: Benchmarking Security Invariants in MCP-Style Agent Runtimes](https://mlsanity.com/paper/2606.29073/) (2026)

## Abstract (arXiv)

Tool-enabled agents form calls from model-visible interfaces, while hosts later select their implementation. Standard dispatch omits the descriptor-handler relation. An unchanged and schema-valid call can therefore acquire a different security effect during rollout, reconnect, or delayed approval. We call this failure schema-epoch drift. We present formation-consistent dispatch (FCD), which connects implementation analysis to execution authority. Reviewed profiles produce provenance-bound over-approximations of declared in-scope effects from official source. Under a closed-target approval policy, a verifier applies each formed call to a summary and captures a successor only when its effects fit the call's security contract. Atomic admission and a final-hop fence preserve this decision to the effect. The exact source retains priority, and the captured successor becomes eligible only after source retirement. Stock releases and deployment changes reproduced the failure. Four profiles covered 32 official releases: 29 required no release-specific change and three escalated. A frozen 16-release expansion matched a separate source oracle. In a preregistered stock comparison, FCD completed all three pending calls whose effect remained private and blocked all three whose omission became public. Exact pinning and release-wide denial stopped all six calls, while release-wide approval completed all six but produced three public effects. A separate lifecycle experiment carried a formation-captured certificate across source retirement. The same safe certificate installed later governed new formations without expanding the pending call's authority.