Moth
Moth is a lightweight MCP server for project-local bug-fix analysis and verified fix memory.
What Moth Does
Moth receives error output through MCP, redacts likely secrets, normalizes the failure, detects the likely stack, checks project-local fix memory, and returns a structured fix brief.
Moth does not edit code, run shell commands, crawl repositories, require a backend, or maintain a global bug database.
Related MCP server: looplens-mcp
Why Moth?
Bug-fix context is often local to a project: the command that failed, the framework in use, nearby configuration, and fixes that have already worked or failed in that repo.
Moth keeps that workflow small and explicit. It analyzes provided error context, suggests a best first fix, and records only verified fix outcomes in project-local memory.
Quick Start
Requires Node.js 18+.
Run directly:
npx -y @stfade/moth moth-mcpOr install globally:
npm install -g @stfade/moth
moth-mcpGeneric MCP config
{
"mcpServers": {
"moth": {
"command": "npx",
"args": ["-y", "@stfade/moth", "moth-mcp"]
}
}
}Usage Example
When using Moth with a supported AI agent, you can include a simple prompt like this along with your error:
"Use Moth to analyze this error before fixing it."
Supported Clients
Client | Status | Setup |
Codex | Local plugin-ready | |
Claude Code | Local plugin-ready | |
Cursor | Plugin scaffold | |
Gemini CLI | Extension scaffold | |
Gemini Antigravity | MCP config-ready | |
OpenCode | MCP config-ready | |
Generic MCP | Config-ready |
“Local plugin-ready” means the integration wrapper is included and can be tested locally. Marketplace submission and approval are not included yet.
Tools
Moth exposes exactly two MCP tools.
analyze_error
Analyzes provided error output before a fix is attempted.
Input fields:
error_outputcommand?cwd?package_context?relevant_files?environment?
Output fields:
analysis_idfingerprintstacklikely_causebest_first_fixverificationprior_project_fixesavoidconfidence
remember_fix_result
Records verified project-local fix memory.
Input fields:
analysis_idfingerprintstackfix_attemptedverification_commandverification_result: "passed" | "failed"notes?
The public worked input is rejected. worked is derived from verification_result.
Verified Memory Lifecycle
analyze_error
→ apply/attempt fix
→ run verification command
→ remember_fix_resultCall remember_fix_result only when:
a fix/change was actually attempted
the verification command actually ran
the result is clearly
passedorfailed
Do not call it for suggestions, skipped changes, missing verification, ambiguous results, or guesses.
Local Memory
Verified project-local fix memory is stored at:
.moth/fix-memory.jsonlMoth keeps a small Moth-owned analysis registry outside the project so remember_fix_result can map analysis_id back to the correct project path after an MCP server restart.
Skills
Moth includes concise skills for compatible agents:
moth-debug-first-fixmoth-source-backed-researchmoth-verify-fix
The MCP server itself does not perform live web research. Compatible agents may use their own search tools, guided by Moth skills, when external sources are needed.
Safety
read-only by default
no source edits
no shell execution
no repo-wide scan
no background watcher
no external service required
redacts likely secrets before analysis, responses, and memory writes
Development
pnpm install
pnpm test
pnpm build
pnpm dev
npm pack --dry-runLicense
MIT
Available Tools
2 toolsanalyze_errorAnalyze ErrorC
Analyze provided error output and return a deterministic project-local fix brief.
| Name | Required | Description | Default |
|---|---|---|---|
| error_output | Yes | ||
| command | No | ||
| cwd | No | ||
| package_context | No | ||
| relevant_files | No | ||
| environment | No |
Output Schema
| Name | Required | Description |
|---|---|---|
| analysis_id | Yes | |
| fingerprint | Yes | |
| stack | Yes | |
| likely_cause | Yes | |
| best_first_fix | Yes | |
| verification | Yes | |
| prior_project_fixes | Yes | |
| avoid | Yes | |
| confidence | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries full burden but only states the output is 'deterministic' and 'project-local'. It does not disclose if the tool modifies state (e.g., reads files, changes anything), required permissions, or potential side effects, leaving agents to infer behaviors.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single concise sentence that front-loads the core purpose. However, it sacrifices critical parameter and usage details, which is a minor structural flaw given the tool's complexity.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Despite having a rich input schema and output schema, the description omits explanation of parameter roles, return format, and usage context. For a complex analysis tool, this is incomplete, though the output schema may partially mitigate return value clarity.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The input schema has 6 parameters with 0% description coverage, yet the description adds no parameter information beyond mentioning 'error output' in the purpose. The other parameters (command, cwd, relevant_files, etc.) remain unexplained, forcing agents to guess their semantics.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the tool analyzes error output and returns a deterministic project-local fix brief. It uses a specific verb ('analyze') and resource ('error output'), and the mention of 'fix brief' distinguishes it from the sibling tool 'remember_fix_result' which likely stores results.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
No guidance on when to use this tool versus the sibling 'remember_fix_result' or other alternatives. The description implicitly suggests using it when an error occurs, but does not specify prerequisites or exclude scenarios.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
remember_fix_resultRemember Fix ResultA
Record verified project-local fix memory only after a fix/change was actually attempted, the verification command was actually run, and the result is clearly passed or failed.
| Name | Required | Description | Default |
|---|---|---|---|
| analysis_id | Yes | ||
| fingerprint | Yes | ||
| stack | Yes | ||
| fix_attempted | Yes | ||
| verification_command | Yes | ||
| verification_result | Yes | ||
| notes | No |
Output Schema
| Name | Required | Description |
|---|---|---|
| recorded | Yes | |
| memory_path | Yes | |
| timestamp | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description discloses that the tool records memory only under specified conditions. However, it lacks details about side effects, authorization needs, or what happens if conditions are unmet. No annotations exist to supplement.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single sentence, front-loaded with the verb and resource, and includes necessary conditional clauses. No redundant information.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the tool has 7 required parameters and no annotations, the description is insufficient. It does not explain what 'fix memory' is, how to obtain analysis_id/fingerprint/stack, or what the output schema contains. An agent would struggle to use this tool correctly.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The schema has 7 parameters with 0% description coverage. The description does not explain any parameters, forcing agents to infer meaning from names alone. This is a significant gap given the tool's complexity.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the tool's purpose: to record a verified fix result after a fix attempt and verification. It specifies the exact conditions (fix attempted, verification run, result passed/failed) and distinguishes from analyze_error.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description provides clear context for when to use: only after a fix is attempted and verification run with a clear result. It does not explicitly state when not to use or mention alternatives, but the conditions are well-defined.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Tool Schema Changelog
Recent tool additions, removals, and schema changes observed during successful MCP inspections. Dates show when Glama detected each change.
2 tool updates
v0.1.0- First observed
analyze_error - First observed
remember_fix_result
TDQS
The two tools have clearly distinct purposes: analyze_error generates a fix brief from error output, while remember_fix_result records the outcome of a fix attempt. There is no overlap or ambiguity.
Both tool names follow a consistent verb_noun pattern in snake_case: analyze_error and remember_fix_result. The naming is clear and predictable.
With only 2 tools, the server feels under-scoped for a typical error analysis workflow. While it may be intentionally minimal, a more comprehensive set would include tools for retrieving fix history or clearing memory.
The tool set lacks retrieval capabilities (e.g., listing or searching past fix results) and memory management (e.g., clearing or updating records). These are notable gaps that could hinder agent workflows.
Maintenance
Resources
Unclaimed servers have limited discoverability.
Looking for Admin?
If you are the server author, to access and configure the admin panel.
Related MCP Connectors
Shared debugging memory for AI coding agents
BugBug skills and MCP workflows for AI agents
Agent Replay Debugger MCP — record every agent step + deterministic replay. Step-debugger for
Structured failure knowledge for AI agents — dead ends, workarounds, error chains
Related MCP Servers
- FlicenseNot gradedqualityCmaintenanceShared debugging memory for AI coding agents. Agents search, report, patch, and verify bug fixes through 5 MCP tools. Verified by proof, not upvotes.1-
- AlicenseBqualityDmaintenanceAn MCP server for detecting retry loops and analyzing iteration patterns in agentic coding workflows, providing structured debugging intelligence to improve repair attempts.164MIT
- AlicenseNot gradedqualityCmaintenanceA deterministic AST evidence engine that forces AI agents to debug using verified execution facts instead of pattern-matching symptoms, enabling hallucination-free debugging for MCP-compatible agents.11Business Source 1.1
- AlicenseNot gradedqualityBmaintenanceAn MCP server that gives coding agents a persistent, chained memory of debugging investigations, tracking what's been tried, ruled out, and solved across sessions and scopes.20MIT
Appeared in Searches
Latest Blog Posts
- Who's Calling? MCP Hosts Are an Identity Blind Spot (And the Spec Knows It)By Om-Shree-0709 on .mcpAgent IdentityOAuth 2.1
- Your AI Chatbot Just Exposed Your CEO's Salary to an InternBy Om-Shree-0709 on .Agent IdentityMCP SecurityOAuth Delegation
- Why MCP Servers Need Execution Sandboxing (And Why Your Current Stack Isn't Enough)By Om-Shree-0709 on .Agentic AiPrompt InjectionWebAssembly
MCP directory API
We provide all the information about MCP servers via our MCP API.
curl -X GET 'https://glama.ai/api/mcp/v1/servers/stfade/moth'
If you have feedback or need assistance with the MCP directory API, please join our Discord server