Repository / project instructions
DocumentedHierarchical context files provide global, workspace, and just-in-time instructions.
View prompt evidenceAgent intelligence
Gemini CLI
Official Gemini CLI evidence covers base-prompt export and replacement, hierarchical GEMINI.md context, dynamic capability injection, tools, and confirmation boundaries.
Official documentation describes Gemini CLI as a configurable terminal agent. Its built-in system prompt can be exported or replaced, GEMINI.md files add hierarchical context, and configured tools and capabilities can be injected dynamically. Mutating actions remain subject to confirmation and configured isolation.
Scope: Gemini CLI · Configurable Gemini model · reviewed Aug 11, 2026
Reviewed product surfaces
Product Surface Schematic
Each layer links to the detailed evidence map. Its state applies only to the reviewed evidence.
Reviewed surface Gemini CLI
- Built-in system promptDocumented
- Dynamic substitutionsDocumented
- GEMINI.md contextDocumented
- ToolsDocumented
- Confirmation and sandboxingDocumented
- Documented
Source-backed answers
Key behaviors
Each answer is scoped to the selected evidence. “Not established” means the evidence does not support the claim; it does not assert absence.
System-prompt replacement
DocumentedGEMINI_SYSTEM_MD replaces, rather than merges with, the built-in default.
View prompt evidenceDynamic context
DocumentedSkills, subagents, and currently enabled tools can be injected into custom system prompts.
View prompt evidenceTools, filesystem, and shell
DocumentedThe official reference covers filesystem, execution, planning, memory, MCP, and web tools.
View prompt evidenceApprovals / permissions
DocumentedMutating tools require confirmation and may run within configured isolation boundaries.
View prompt evidenceEditorial guidance
What this means in practice
These conservative editorial implications come from the linked evidence. They add no vendor claims or generic prompt advice.
Editorial implication
Place scoped project guidance in the GEMINI.md hierarchy.
Global, workspace, and just-in-time context files are the documented mechanism for persistent project and task instructions.
Supporting evidenceEditorial implication
Treat a configured system prompt as a replacement, not an additive layer.
GEMINI_SYSTEM_MD replaces the built-in prompt, so a custom file must carry the instructions the workflow still requires.
Supporting evidenceEditorial implication
Expect runtime configuration to change assembled context and controls.
Enabled skills, subagents, tools, context files, confirmation, and sandbox settings can change the effective workflow.
Supporting evidenceUseful next actions
Continue your research
Compare agent behaviorsReview the same evidence-backed questions across all six products.
Inspect instruction evidenceThe instruction page maps the documented assembly; no exported default prompt is bundled or executed.
How does Gemini CLI compare with Claude Code?Compare prompt handling, project instruction hierarchies, dynamic context, tools, and memory.
How does Codex state its approval boundary?Inspect the corresponding first-party prompt excerpt.
Review source and provenance detailsVerify origin, retrieval, completeness, publication limits, and rights.
Product scope
Gemini CLI's instruction assembly is configurable; the product and selected model remain separate.
- Organization
- Product
- Open-source agentic command-line interface
- Surface
- Gemini CLIAn open-source terminal agent whose prompt and context assembly can vary with configuration.
- Model context
- Configurable Gemini modelThe selected documentation describes the CLI instruction architecture rather than pinning one universal model snapshot.
Evidence status
Coverage and review
Official documentation covers prompt export and replacement, dynamic substitutions, GEMINI.md context, and tools. The review does not claim one immutable runtime prompt.
- Coverage
- partial
- Primary source
- Tier A · vendor-published
- Review freshness
- currentOfficial Gemini CLI documentation was reviewed for prompt override/export, GEMINI.md hierarchy, and tools.
- Reviewed
- Aug 11, 2026
Detailed instruction layers
Instruction-system map
The instruction map separates the built-in prompt, full override, injected capabilities, hierarchical project context, and harness-level confirmation controls.
Built-in system promptdocumented
The CLI can export the current built-in prompt and completely replace it with a configured Markdown file.
EvidenceDynamic substitutionsdocumented
Skills, subagents, and currently enabled tools can be injected into custom system prompts.
EvidenceGEMINI.md contextdocumented
Hierarchical context files provide global, workspace, and just-in-time instructions.
EvidenceToolsdocumented
The official reference covers filesystem, execution, planning, memory, MCP, and web tools.
EvidenceConfirmation and sandboxingdocumented
Mutating tools require confirmation and may run within configured isolation boundaries.
EvidenceSupporting instruction evidence
Prompt and snapshot evidence
The instruction page maps the documented assembly; no exported default prompt is bundled or executed.
Inspect instruction evidence- Selected snapshot
- Gemini CLI instruction assembly · reviewed August 11, 2026
- Evidence coverage
- Through Aug 11, 2026Gemini CLI instruction assembly · reviewed August 11, 2026
- Latest known vendor version
- Not established by selected evidence
- Current product state
- Not established by selected evidence
- Publication
- Documentation-derived analysis
- Instruction page
- Available and indexableFirst-party documentation establishes a substantial, unique prompt-assembly record with explicit limitations.
Evidence-backed capabilities
Capabilities with evidence
Each capability links to its supporting instruction section and keeps its stated confidence level.
| Capability | What the source establishes | Confidence | Evidence |
|---|---|---|---|
| Built-in prompt export | GEMINI_WRITE_SYSTEM_MD writes the current built-in prompt to a reviewable file. | high | Section |
| Complete system-prompt override | GEMINI_SYSTEM_MD replaces, rather than merges with, the built-in default. | high | Section |
| Hierarchical GEMINI.md context | Global, workspace, and just-in-time files provide scoped instructional context. | high | Section |
| Dynamic capability injection | Configured skills, subagents, and enabled tools can be substituted into a custom system prompt. | high | Section |
| Approval-aware tool execution | Mutating file and shell tools require confirmation under the documented default posture. | high | Section |
Version evidence
Snapshots and meaningful changes
The reviewed live documentation does not expose a compatible immutable prompt history in the selected evidence.
- selected Gemini CLI instruction assembly · reviewed August 11, 2026Reviewed Aug 11, 2026Instruction evidence
Provenance
Source ledger
Every source lists its origin, retrieval date, completeness, publication limits, and rights separately.
Tier A · vendor-published
Gemini CLI system-prompt override documentation
- Publisher
- Retrieved
- Aug 11, 2026
- Upstream ref
- Official documentation last updated 2026-06-18; reviewed 2026-08-11
- Rights posture
- Original summary of official documentation; no exported prompt collected or reproduced.
Documents export, replacement, and substitutions but does not itself provide one immutable runtime prompt.
Open primary source Tier A · vendor-published
Gemini CLI GEMINI.md context documentation
- Publisher
- Retrieved
- Aug 11, 2026
- Upstream ref
- Official documentation last updated 2026-06-18; reviewed 2026-08-11
- Rights posture
- Original summary of official documentation.
Covers context-file hierarchy, not the complete prompt assembly.
Open primary source Tier A · vendor-published
Gemini CLI tools reference
- Publisher
- Retrieved
- Aug 11, 2026
- Upstream ref
- Live official documentation reviewed 2026-08-11
- Rights posture
- Original summary of official documentation.
Tool availability can vary by configuration and version.
Open primary source