dead-letter
MCPB · DEAD-LETTER-MCP-0.4.10.MCPB · 3 COMPONENTS
Convert .eml and .mbox email to clean Markdown for RAG, LLM pipelines, and local knowledge bases
Last scanned (6 hours ago)
Scores higher than 75% of MCPB servers
Category Documents and Files
How this component scores in each security and reliability category. Every signal is checked automatically from public evidence about the published package, including repeated runs of it in an isolated sandbox, and we only credit what we can confirm. How we score → Why this is hard to score →
Supply Chain Security12
- No malware scan is available for this kind of package: the supply-chain vendors we use do not cover it. This is a permanent gap in our coverage, not a finding about the package.Unverified
- Known CVEs were checked across the 38 of 38 dependencies we could resolve, so this covers what we could see, not the whole tree.Partial
- Install-script risk not yet assessed.Unverified
- 1 of 38 dependencies flagged as unhealthy. View diagnostics → Partial
Provenance & Transparency35
- Source repository is publicly reachable at the declared URL. View diagnostics → Pass
- Provenance check failed: no build-provenance attestation is published. See how to fix → View diagnostics → Fail
- License check failed: the license (PolyForm-Noncommercial-1.0.0) isn't a recognized OSI-approved license. See how to fix → Fail
- Actively maintained (last published 6 days ago).Pass
- Publishes a security disclosure policy (SECURITY.md).Pass
Schema Quality & AI Usability42
- AI-judged instruction clarity (fair).Partial
- Context-footprint check failed: tool/resource definitions use about 1222 tokens (~244/item across 5 items; 5 tools + 0 resources), over budget; trim descriptions and params. See how to fix → Fail
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management73
- Stability observed for 22 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage71
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 0% of tool parameters carry a description.Fail
- Structured output schemas are declared (100% of tools); any adoption earns full credit.Pass
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- We read all 5 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 5 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
- Implements a current MCP spec version (2026-07-28).Pass
Checks we ran (14)
- Known CVEs
- Dependency health
- Source repository
- Provenance
- License
- Maintenance
- Security disclosure
- Schema quality
- Stability
- Tool coverage
- Injection markers
- Destructive annotations
- Judged manipulation
- MCP protocol
Checks we could not complete (2)
These are gaps on our side, not findings about this package. We only credit what we can confirm, so a category made up entirely of them scores 0.
- Malware scan in Supply Chain SecurityNo malware scan is available for this kind of package: the supply-chain vendors we use do not cover it. This is a permanent gap in our coverage, not a finding about the package.
- Install scripts in Supply Chain SecurityInstall-script risk not yet assessed.
Does not apply to this package (2)
- Endpoint SecurityScored on hosted endpoints only. A package has no live endpoint of its own for us to probe.
- Transport & ReachabilityScored on hosted endpoints only. A package has no live endpoint of its own for us to probe.
The score does not measure everything. What the score does not measure →
Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.
- 4 Nov 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 67 to 70. That category is still filling its 30-day observation window: 20 days of observed history at the previous scan, 21 at this one. The score rises as the window fills, whether or not the server changes.
- 3 Nov 26 −5
- Stability: pass → 0.67 functional
- 29 Oct 26 0
- Package version: 0.4.9 → 0.4.10 functional
- 28 Oct 26 +1
- Stability: 0.97 → pass security
- 26 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 90 to 93. That category is still filling its 30-day observation window: 27 days of observed history at the previous scan, 28 at this one. The score rises as the window fills, whether or not the server changes.
- 24 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 83 to 87. That category is still filling its 30-day observation window: 25 days of observed history at the previous scan, 26 at this one. The score rises as the window fills, whether or not the server changes.
- 23 Oct 26 0
- Package version: 0.4.8 → 0.4.9 functional
- 22 Oct 26 0
- Package version: 0.4.8 → 0.4.9 functional
Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.
Captured 5 Nov 2026 · Analysed mcpb/https://github.com/BigCactusLabs/dead-letter/releases/download/v0.4.10/dead-letter-mcp-0.4.10.mcpb@0.4.10
Provenance No attestation
The registry publishes no build provenance for this version, so there is nothing to verify.
| Result | No attestation |
|---|---|
| Ecosystem | mcpb |
| Reason | No attestation published |
Background: How many MCP packages publish verified provenance →
Dependencies 38 packages
| Packages resolved | 38 |
|---|---|
| No linked repository | 1 |
| Tree resolution | Complete |
Background: SBOMs and build attestations, explained →
The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →
convert_directory Convert email folder ~233
Batch convert all .eml files in a directory to Markdown. Recursively finds .eml files (at most 50 per call; larger directories are rejected before any conversion). output_directory is required: Markdown is written there, mirroring subfolders, and source .eml files are left in place. Returns a JSON summary with total, successes, failures, output_paths, and errors. Each errors entry contains file and error_code (defaulting to conversion_error), never raw exception text. Use convert_eml to retrieve individual converted file content.
| Name | Type | Req | Description |
|---|---|---|---|
| directory | string | yes | – |
| dry_run | boolean | – | – |
| embed_inline_images | – | – | – |
| include_all_headers | – | – | – |
| include_raw_html | – | – | – |
| no_calendar_summary | – | – | – |
| output_directory | string | yes | – |
| preset | string | – | – |
| strip_disclaimers | – | – | – |
| strip_quoted_headers | – | – | – |
| strip_signature_images | – | – | – |
| strip_signatures | – | – | – |
| strip_tracking_pixels | – | – | – |
| thread_mode | string | – | – |
| thread_order | string | – | – |
| Name | Type | Req | Description |
|---|---|---|---|
| result | string | yes | – |
No examples provided.
convert_eml Convert email ~280
Convert a .eml email file to Markdown with YAML front matter. Returns the full Markdown content (front matter + body). When output_path is provided, also writes the file to disk. Attachments are listed in the front matter but not written to disk; use convert_eml_to_bundle to save the decoded attachment files. thread_mode="structured" adds a section per earlier reply or forwarded message. Gmail HTML forwards and unquoted plain-text forwards are kept in latest mode too; a plain-text forward inside ">" quoting is not. Presets bundle common flag combinations: - default: strips signatures, tracking pixels, signature images - clean: default + strips disclaimers and quoted headers - verbose: includes all headers and raw HTML - raw: no stripping, preserves everything Individual flags override the preset when provided.
| Name | Type | Req | Description |
|---|---|---|---|
| embed_inline_images | – | – | – |
| eml_path | string | yes | – |
| include_all_headers | – | – | – |
| include_raw_html | – | – | – |
| no_calendar_summary | – | – | – |
| output_path | – | – | – |
| preset | string | – | – |
| strip_disclaimers | – | – | – |
| strip_quoted_headers | – | – | – |
| strip_signature_images | – | – | – |
| strip_signatures | – | – | – |
| strip_tracking_pixels | – | – | – |
| thread_mode | string | – | – |
| thread_order | string | – | – |
| Name | Type | Req | Description |
|---|---|---|---|
| result | string | yes | – |
No examples provided.
convert_eml_to_bundle Convert email to bundle ~229
Convert a .eml file to a self-contained bundle with markdown and attachments. Creates a directory containing the converted markdown, extracted attachments, and optionally the original .eml source. source_handling only accepts 'copy' over MCP: the original .eml is copied into the bundle and left untouched. The 'move' and 'delete' modes are rejected here — use the CLI or the Python API for those. Returns JSON with bundle_path, markdown_path, attachment_paths, and optional diagnostics.
| Name | Type | Req | Description |
|---|---|---|---|
| bundle_root | string | yes | – |
| embed_inline_images | – | – | – |
| eml_path | string | yes | – |
| include_all_headers | – | – | – |
| include_raw_html | – | – | – |
| no_calendar_summary | – | – | – |
| preset | string | – | – |
| source_handling | string | – | – |
| strip_disclaimers | – | – | – |
| strip_quoted_headers | – | – | – |
| strip_signature_images | – | – | – |
| strip_signatures | – | – | – |
| strip_tracking_pixels | – | – | – |
| thread_mode | string | – | – |
| thread_order | string | – | – |
| Name | Type | Req | Description |
|---|---|---|---|
| result | string | yes | – |
No examples provided.
convert_mbox Convert MBOX archive ~282
Convert one flat .mbox archive (e.g. Gmail Takeout) to Markdown files. Bounded: the archive must be at most 256 MiB, and conversion stops after 1000 messages (the response then has truncated=true; use the dead-letter CLI for larger archives). Compressed archives and Apple Mail .mbox directories are rejected. output_directory is required; one .md per message (or one bundle directory when bundles=true) is written there with a collision-safe JSON report. The source archive is never modified. Returns a JSON summary (processed, converted, skipped, failed, truncated, report_path, and at most 20 failure entries), never message content. Cancellation is not supported; byte/message caps are not a time limit.
| Name | Type | Req | Description |
|---|---|---|---|
| bundles | boolean | – | – |
| dry_run | boolean | – | – |
| embed_inline_images | – | – | – |
| include_all_headers | – | – | – |
| include_raw_html | – | – | – |
| no_calendar_summary | – | – | – |
| output_directory | string | yes | – |
| path | string | yes | – |
| preset | string | – | – |
| strip_disclaimers | – | – | – |
| strip_quoted_headers | – | – | – |
| strip_signature_images | – | – | – |
| strip_signatures | – | – | – |
| strip_tracking_pixels | – | – | – |
| thread_mode | string | – | – |
| thread_order | string | – | – |
| Name | Type | Req | Description |
|---|---|---|---|
| result | string | yes | – |
No examples provided.
get_diagnostics Get conversion diagnostics ~198
Inspect email quality and structure without writing permanent files. Use this to assess conversion quality before committing, or to troubleshoot problematic .eml files. Always returns JSON with: state (normal/degraded/review_recommended), selected_body, segmentation_path, client_hint, confidence, fallback_used, and warnings. Two keys are conditional: stripped_images appears only when images were removed, and attachments only when the message had attachments eligible for retention.
| Name | Type | Req | Description |
|---|---|---|---|
| embed_inline_images | – | – | – |
| eml_path | string | yes | – |
| include_all_headers | – | – | – |
| include_raw_html | – | – | – |
| no_calendar_summary | – | – | – |
| preset | string | – | – |
| strip_disclaimers | – | – | – |
| strip_quoted_headers | – | – | – |
| strip_signature_images | – | – | – |
| strip_signatures | – | – | – |
| strip_tracking_pixels | – | – | – |
| thread_mode | string | – | – |
| thread_order | string | – | – |
| Name | Type | Req | Description |
|---|---|---|---|
| result | string | yes | – |
No examples provided.
How do I install the dead-letter MCP server?
dead-letter ships as an MCPB bundle, a single file you download and open in an MCP host that supports MCPB bundles, such as Claude Desktop. The host reads the launch command from the bundle's own manifest, so there is no command to copy. Before opening it, check the file's SHA-256 matches the one the MCP registry declares for it, 2cbeab1f2b0e499b034e708bb50aa5ce5862b2c4591babc54b4b2106f6257168; the commands to do that are on this page. If it does not match, do not open it.
mcpb · dead-letter-mcp-0.4.10.mcpb
Download bundleCheck the download matches the SHA-256 the MCP registry declares before you open it. If it does not match, do not open the file.
SHA-256
2cbeab1f2b0e499b034e708bb50aa5ce5862b2c4591babc54b4b2106f6257168
macOS / Linux
echo "2cbeab1f2b0e499b034e708bb50aa5ce5862b2c4591babc54b4b2106f6257168 dead-letter-mcp-0.4.10.mcpb" | shasum -a 256 -c
Windows (PowerShell)
(Get-FileHash -Algorithm SHA256 .\dead-letter-mcp-0.4.10.mcpb).Hash -eq "2cbeab1f2b0e499b034e708bb50aa5ce5862b2c4591babc54b4b2106f6257168"
Run it in the folder you saved the bundle to, then open the file with an MCPB-capable host such as Claude Desktop.
What is the dead-letter MCP server?
dead-letter is an MCP server listed in the public MCP registry as io.github.BigCactusLabs/dead-letter. Convert .eml and .mbox email to clean Markdown for RAG, LLM pipelines, and local knowledge bases. This page covers its MCPB bundle (https://github.com/BigCactusLabs/dead-letter/releases/download/v0.4.10/dead-letter-mcp-0.4.10.mcpb).
Is the dead-letter MCP server safe to use?
dead-letter scores 44 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.
What tools does the dead-letter MCP server expose?
dead-letter exposes 5 tools: convert_eml, convert_eml_to_bundle, convert_directory, convert_mbox, get_diagnostics. Their descriptions and schemas cost roughly 1,222 tokens of context every time the server is loaded.
What licence is the dead-letter MCP server under?
dead-letter declares the PolyForm-Noncommercial-1.0.0 licence, which is not on the OSI-approved list. Read the terms before using it at work, and note this covers the source only, not the cost of any service it calls.
What did VerifyMCP test on the dead-letter MCP server?
VerifyMCP ran 14 checks on dead-letter, covering Known CVEs, Dependency health, Source repository, Provenance and 10 more. 2 items could not be completed, a gap on our side rather than a finding about dead-letter: Malware scan and Install scripts. Endpoint Security and Transport & Reachability do not apply to an MCPB bundle, so they were not tested. The score does not measure everything, and the scoring documentation lists what it leaves out.