[Jose Alvarez (jpalvarezl)]

Motivation & Context

An agent configured with multiple FileAccessProvider instances fails while merging tools because every provider exposes the same file_access_* names, even when the providers have distinct source IDs and independently rooted stores.

Allow callers to distinguish each provider's tools so an agent can access multiple file stores without tool-name collisions.

Description & Review Guide

• What are the major changes?
  • Add an optional, keyword-only tool_name_prefix constructor parameter to FileAccessProvider and apply it to all eight registered tool names.
  • Keep the existing names when the prefix is omitted or empty. A prefix such as spec produces names such as spec_file_access_read.
  • Add regression coverage for the issue reproduction, distinct prefixes, prefixed/default provider coexistence, all eight tool names, and reads/writes routed to the correct store.
• What is the impact of these changes?
  • Providers with distinct tool names can coexist on one agent without changing the default tool names or shared class constants.
  • Distinct source IDs alone still do not prevent collisions; callers must configure distinct prefixes when combining providers.
• What do you want reviewers to focus on?
  • Prefix semantics, backward compatibility, and correct per-store routing.
  • This is a draft: default instructions and the static auto-approval rules still refer to the original, unprefixed names. Those surfaces need to be aligned with prefixed names before the change is ready for review. The auto-approval mismatch fails closed and leaves approval required.

Related Issue

Fixes #9646

Maintainer agreement with the direction was explicitly confirmed by the submitter during preparation of this draft. No competing open PR was found for the issue.

AI Assistance

• No material AI assistance was used.
• This is an AI-assisted contribution. I reviewed, understood, and verified all submitted content and accept responsibility for it.

AI assistance details: GitHub Copilot assisted with code analysis and review, regression tests, validation, and this PR description. The implementation was authored by the contributor.

Contribution Checklist

• The code builds clean without any errors or warnings
• All unit tests pass, and I have added new tests where possible
• The PR follows the Contribution Guidelines
• This PR links to an agreed issue with no competing open PR, or the Related Issue section documents a trivial-change or repository-automation exception.
• This is not a breaking change. If it is a breaking change, add the breaking change label (or add "[BREAKING]" to the title prefix, before or after any language prefix) — a workflow keeps the label and title prefix in sync automatically.

The focused file-access unit test module passes: 131 passed, 7 skipped, with three existing warnings. Ruff lint/format checks and Pyright pass for both changed files. The full core unit suite and a package build have not been run, so their checklist items remain unchecked.

[github-code-quality]

Code coverage overview

Languages: Python

Python / code-coverage/python

main bdf5256	jpalvarezl/fix/issue... f1e886c	+/-
92%	92%	0%

ℹ️ Calculations represent line coverage. Results may change as calculations are updated.

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_{Updated October 26, 2026 12:30 UTC}

[Copilot]

🟡 Changes recommended

Model-facing guidance and auto-approval rules still use unprefixed names and need to support the configured prefixes.

2 open issues

• Render built-in guidance with prefixed tool names · New
• Support prefixed names in public auto-approval rules · New

What changed in this PR

Adds optional tool-name prefixes to Python’s FileAccessProvider, addressing #9646 by allowing independently rooted stores to coexist on one agent without tool-name collisions.

Changes:

• Adds keyword-only tool_name_prefix and applies it to all eight tools.
• Preserves existing tool names when the prefix is omitted or empty.
• Adds regression coverage for collisions, mixed provider configurations, and per-store read/write routing.

File	Description
python/​packages/​core/​tests/​core/​test_harness_file_access.py	Tests prefix naming, provider coexistence, and isolated store routing.
python/​packages/​core/​agent_framework/​_harness/​_file_access.py	Adds prefix configuration and applies it during tool registration.

_{Review effort: Balanced}

[github-actions]

MAF Automated Review — Iteration 1

Result: Findings reported
Scope: full PR (1 commit(s)): 5e1d6a75ec8b
Model: gpt-5.6-sol

Overview

The PR consistently applies the configured prefix to all eight tools, preserves default names for falsey prefixes, rejects remaining duplicate names centrally, and tests per-store routing. However, renaming leaves the public auto-approval rules authoritative over the old names, which can bypass approval for an unrelated local tool, while the default model instructions still advertise those old names. Prefixes are also accepted verbatim even when they produce names rejected by model providers.

Reviewed the supplied pull-request change set across correctness, security/reliability, architecture, and failure behavior.
3 verified findings remained after source verification (1 high, 2 medium) across 1 file. Details are attached to the affected lines below.

Affected areas: python/packages/core/agent_framework/_harness/_file_access.py