SubDownload
Server Details
SubDownload exposes YouTube as an MCP-native data source. Connect via OAuth and your AI agent can summarize videos, fetch full transcripts (even for videos with no captions, via AI ASR), search across channels, and save everything into a private knowledge base. Works with Claude, ChatGPT, Cursor, and 40+ MCP clients. Free credits on signup, no card required.
- Status
- Healthy
- Last Tested
- Transport
- Streamable HTTP
- URL
Glama MCP Gateway
Connect through Glama MCP Gateway for full control over tool access and complete visibility into every call.
Full call logging
Every tool call is logged with complete inputs and outputs, so you can debug issues and audit what your agents are doing.
Tool access control
Enable or disable individual tools per connector, so you decide what your agents can and cannot do.
Managed credentials
Glama handles OAuth flows, token storage, and automatic rotation, so credentials never expire on your clients.
Usage analytics
See which tools your agents call, how often, and when, so you can understand usage patterns and catch anomalies.
Tool Definition Quality
Average 4.3/5 across 13 of 13 tools scored.
Each tool has a clearly distinct purpose: fetching transcripts, video info, ASR task polling, channel and library listing, searching, etc. No overlapping functionality.
All tool names follow a consistent verb_noun pattern (e.g., fetch_transcript, list_channel_videos, resolve_channel) with snake_case. No mixing of styles.
13 tools is well-scoped for a YouTube subtitle server. It covers transcript, info, search, and library management without being bloated.
The tool surface covers the full lifecycle: fetching transcripts (via captions or ASR), video metadata, searching across channels/playlists/YouTube, and library operations. No obvious gaps for the server's stated purpose.
Available Tools
15 toolsfetch_transcriptARead-onlyInspect
Fetch the full transcript (subtitles/captions) of a YouTube video in any language. ALWAYS call this when the user shares ANY YouTube link (youtube.com, youtu.be, shorts). Also use when the user wants to: summarize a video, know what was said, quote or cite video content, translate video dialogue, fact-check claims, study a lecture or tutorial, extract key points, analyze speaker arguments, or any task involving the spoken content of a video. Pass save=true to also bookmark the video into the user's Library in the same call (upserts the meta row; when the result came from ASR fallback it also flags has_asr). Saves a follow-up save_to_library round-trip.
| Name | Required | Description | Default |
|---|---|---|---|
| lang | No | Language code (e.g. en, zh, ja). Omit for default language. | |
| save | No | When true, also save the video to the user's Library in the same call. Bookmarks the meta row and flips has_asr when the transcript was produced by our ASR. Does NOT upload a summary — use save_to_library with kind='summary' or kind='both' for that. | |
| video_id | Yes | YouTube video ID (e.g. dQw4w9WgXcQ) or full YouTube URL |
Tool Definition Quality
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Adds behavioral context beyond annotations: explains that save=true upserts a meta row and flags has_asr on ASR fallback. Annotations already declare readOnlyHint=true, but the description clarifies that the primary operation is read-only with an optional write side effect. No contradiction.
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 front-loaded with the core purpose, then follows with usage guidelines and parameter details. It is somewhat lengthy due to the exhaustive use-case list, but every sentence adds value. Minor room for tightening.
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 no output schema, the description could explain the return format, but it is a standard transcript string. The description covers when to use, parameter semantics, and side effects thoroughly, making it sufficiently complete for effective tool selection and invocation.
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?
Schema coverage is 100%, and the description adds significant value: explains the save parameter's side effects (upsert, has_asr flag) and that it saves a follow-up round-trip. This enhances understanding beyond the schema descriptions.
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 it fetches the full transcript of a YouTube video. It uses specific verb+resource ('Fetch the full transcript') and distinguishes from siblings like fetch_video_info (metadata) and transcribe_video (audio transcription) by targeting video transcripts.
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?
Explicitly says 'ALWAYS call this when the user shares ANY YouTube link' and lists numerous use cases (summarize, quote, translate, etc.). While it doesn't explicitly state when not to use, the exhaustive list of use cases and the sibling tools provide clear guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
fetch_video_infoARead-onlyInspect
Fetch consolidated YouTube video metadata with numeric types — duration_seconds (int), view_count (int64), published_at (RFC3339). Use when you need exact numbers for sorting/analytics instead of YouTube's display strings ('1.2M views', '2 weeks ago'). Title, description, channel_id, channel_title, thumbnail, and is_live are included too. Costs 1 credit.
| Name | Required | Description | Default |
|---|---|---|---|
| video_id | Yes | 11-char video ID or full YouTube URL (watch, youtu.be, shorts, embed, live) |
Tool Definition Quality
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Description adds value beyond annotations by detailing return types (int, int64, RFC3339) and listing included fields (title, description, channel_id, etc.). Annotations already declare readOnlyHint=true and destructiveHint=false, so description complements without contradiction. Could mention error handling but is sufficiently transparent.
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?
Three succinct sentences: first states purpose and key returns, second gives usage guidance, third notes cost. No wasted words, front-loaded with critical info.
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 simple single-parameter tool with no output schema, the description adequately covers purpose, when to use, return fields, and cost. Lists specific fields (duration_seconds, view_count, published_at, etc.) that the agent can expect, making it complete.
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?
Input schema has 100% coverage with a detailed description of video_id. The tool description does not add new parameter semantics; it focuses on return values. Baseline 3 for high schema coverage is appropriate.
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?
Description clearly states 'Fetch consolidated YouTube video metadata with numeric types', which is a specific verb and resource. It distinguishes from siblings by highlighting numeric fields vs. YouTube's display strings, differentiating from tools like fetch_transcript or search_youtube.
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?
Explicitly says 'Use when you need exact numbers for sorting/analytics instead of YouTube's display strings', providing clear context for when to select this tool over alternatives. Also mentions cost, aiding decision-making.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
get_asr_taskARead-onlyInspect
Poll the status of an ASR task created by transcribe_video. Returns current status, segments (when done), and next_poll_after_seconds. If status is not 'done'/'failed'/'cancelled', wait next_poll_after_seconds then call again. Free — no credits charged.
| Name | Required | Description | Default |
|---|---|---|---|
| task_id | Yes | Task ID returned by transcribe_video. |
Tool Definition Quality
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Discloses polling behavior, return fields (status, segments, next_poll_after_seconds), and free operation. Annotations already indicate readOnlyHint=true and non-destructive, and description adds valuable behavioral context without contradiction.
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?
Three sentences, efficient and front-loaded. Every sentence adds value: purpose, return fields, and usage guidance. No waste.
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?
For a simple poll tool with one parameter and no output schema, the description covers all necessary aspects: input (task ID from transcribe_video), output fields, and usage pattern. Complete and self-contained.
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?
Schema has 100% coverage for the single parameter (task_id). Description adds context that the task ID comes from transcribe_video and this tool is for polling, which is beyond the schema's description.
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?
Description clearly states polling a specific ASR task created by transcribe_video. Verb 'Poll' and resource 'ASR task' are explicit, distinguishing it from siblings like transcribe_video (creator) and fetch_transcript (potential consumer).
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?
Explicit polling loop instructions: if status not terminal, wait next_poll_after_seconds and retry. Also notes no credit charge. Lacks explicit comparison to alternatives (e.g., fetch_transcript) but provides solid context for use.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
get_channel_latest_videosARead-onlyInspect
Get the most recent videos from a YouTube channel. Use when the user asks what a creator has posted recently, wants latest uploads, asks 'what's new on [channel]', or when you need to find a recent video to then fetch its transcript. Free, no credits consumed.
| Name | Required | Description | Default |
|---|---|---|---|
| channel | Yes | @handle, channel URL, or UC... channel ID |
Tool Definition Quality
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already indicate read-only and non-destructive. Description adds cost info ('Free, no credits consumed') but no extra behavioral details beyond annotations.
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?
Two efficient sentences: purpose first, then usage and cost. No wasted words, front-loaded.
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?
Covers purpose, usage, and cost. Lacks output format details but for a simple retrieval tool with good annotations, it's mostly complete.
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?
Schema covers 100% with parameter description. Description does not add additional meaning; baseline 3 applies.
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?
Describes specific verb 'get' and resource 'most recent videos from a YouTube channel'. Distinct from siblings like list_channel_videos and search_channel_videos by focusing on recency.
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?
Explicitly lists use cases (recent uploads, 'what's new', fetching transcript) and states cost. No alternatives mentioned but context is clear.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
get_library_itemARead-onlyInspect
Read a saved Library item with its transcript and summary inline (when available). Use after list_library to read the actual content the user saved. Free.
| Name | Required | Description | Default |
|---|---|---|---|
| id | Yes | Library item id (from list_library). | |
| locale | No | Summary locale to fetch (e.g. en, zh). Defaults to en. |
Tool Definition Quality
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already mark as readOnlyHint=true; description adds that transcript and summary are returned 'inline (when available)', which is useful. Also mentions 'Free'. No contradiction with annotations.
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?
Two sentences, front-loaded with main action and key features. No extraneous words. Highly efficient.
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 simplicity (2 params, read-only, no output schema), the description adequately covers return value (transcript and summary). Minor omission: no mention of error handling or missing items, but standard for a tool of this type.
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?
Schema description coverage is 100%; both parameters have descriptions in schema. The tool description adds no new parameter-specific info beyond the schema, so baseline of 3 is appropriate.
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 it reads a saved Library item with transcript and summary inline. It distinguishes from sibling tools like list_library by specifying 'use after list_library to read the actual content'.
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?
Explicitly says 'Use after list_library', giving clear context for when to invoke. Does not specify when not to use or mention alternatives, but the context is sufficient given sibling tools are quite different.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
list_channel_videosARead-onlyInspect
List all videos from a YouTube channel with pagination. Use when the user wants to browse all videos from a channel. Costs 1 credit per page.
| Name | Required | Description | Default |
|---|---|---|---|
| channel | No | @handle, channel URL, or UC... ID. Required for first page. | |
| continuation | No | Pagination token from previous response. Required for subsequent pages. |
Tool Definition Quality
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Beyond annotations (readOnlyHint=true), description adds 'Costs 1 credit per page' and mentions pagination, revealing cost and behavior. No contradiction with annotations.
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?
Two concise sentences, zero wasted words. Front-loaded with action verb 'List'. Efficiently communicates key 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 simple tool with complete schema and annotations, the description adequately covers purpose, cost, and pagination. No output schema needed; agent can infer return format.
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?
Schema coverage is 100% with clear descriptions for both parameters. Description does not add additional parameter details beyond what schema provides, so baseline score is appropriate.
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?
Description states 'List all videos from a YouTube channel with pagination', which clearly defines a specific verb (list) and resource (videos from a channel), and distinguishes from sibling tools like 'list_playlist_videos' and 'search_channel_videos'.
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?
Directly says 'Use when the user wants to browse all videos from a channel', providing explicit context for when to invoke. Does not explicitly mention alternatives or when not to use, but the usage instruction is clear.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
list_libraryARead-onlyInspect
List videos the user has saved to their Library (transcripts + summaries). Use when the user asks about their saved content, wants to revisit a past video, or asks 'what have I saved'. Free.
| Name | Required | Description | Default |
|---|---|---|---|
| q | No | Substring match on title/author. | |
| limit | No | Max items (1-100, default 20). | |
| offset | No | Pagination offset. | |
| favorite | No | Filter to favorited items only. |
Tool Definition Quality
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, so description adds value by noting content type (transcripts+summaries) and 'Free'. No additional behavioral details like pagination or ordering, but adequate.
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?
Two sentences, front-loaded with purpose, then usage context. 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?
For a listing tool with no output schema and well-documented parameters, the description covers purpose and usage context. Could mention pagination default or ordering, but not critical.
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?
Input schema has 100% coverage with descriptions for all 4 parameters. The description does not add extra parameter semantics beyond the schema, so baseline score is appropriate.
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 it lists videos saved to the Library, including transcripts and summaries. It distinguishes from siblings like search_youtube or list_channel_videos by focusing on saved content.
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?
Explicitly provides usage scenarios (user asks about saved content, wants to revisit, or asks 'what have I saved'). Lacks explicit exclusions but context is clear.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
list_playlist_videosARead-onlyInspect
List videos in a YouTube playlist with pagination. Use when the user shares a playlist link or asks about playlist contents. Costs 1 credit per page.
| Name | Required | Description | Default |
|---|---|---|---|
| playlist | No | Playlist URL or ID (PL..., UU...). Required for first page. | |
| continuation | No | Pagination token from previous response. Required for subsequent pages. |
Tool Definition Quality
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already indicate readOnly and non-destructive nature. The description adds behavioral details like pagination and credit cost per page, which are not in annotations. No contradictions.
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 two sentences: first states purpose concisely, second provides usage guidance and cost. No unnecessary words, front-loaded.
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's simplicity with two optional parameters and annotations present, the description covers purpose, usage, and cost. It lacks details on the response format, but the rest is sufficient.
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?
Schema coverage is 100% with descriptions for both parameters. The description does not add additional meaning beyond what the schema provides, so baseline score of 3 is appropriate.
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 explicitly states the tool lists videos in a YouTube playlist with pagination, which clearly identifies the verb and resource. It distinguishes from siblings like list_channel_videos by focusing on playlist content.
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 explicit usage guidance: 'Use when the user shares a playlist link or asks about playlist contents.' It gives context but does not mention when not to use or alternative tools.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
resolve_channelARead-onlyInspect
Resolve a YouTube @handle, channel URL, or video link to get channel information. Use when the user mentions ANY YouTuber, creator, channel name, or @handle. Also use to identify which channel uploaded a specific video. Free, no credits consumed.
| Name | Required | Description | Default |
|---|---|---|---|
| input | Yes | @handle (e.g. @MrBeast), channel URL, video URL, or UC... channel ID |
Tool Definition Quality
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and destructiveHint=false. Description adds that it costs no credits, which is valuable behavioral context for an AI agent. No contradiction.
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?
Two sentences, economical with words, front-loaded with the core action. No extraneous 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 single parameter and no output schema, the description fully covers the tool's functionality, usage scenarios, and side effects. No gaps.
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?
Schema coverage is 100% and already describes the input parameter with examples. Description repeats the input types but does not add significant new meaning beyond the schema.
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?
Description clearly states the tool resolves YouTube handles, channel URLs, or video links to channel info. It specifies the input types and distinguishes from sibling tools which focus on video/transcript data.
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?
Explicitly tells when to use: when user mentions any YouTuber, creator, or to identify video uploader. Also mentions it's free. Does not explicitly list when not to use or alternative tools.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
save_to_libraryAIdempotentInspect
Save a video to the user's Library. Three modes: kind='asr' (mark the saved transcript — ASR must have already finished); kind='summary' (upload your generated summary text to persist it); kind='both' (one call: flag the transcript AND upload the summary — use this right after summarizing a video you just transcribed, it saves a round-trip and one quota unit). Costs one API call unit; no credits.
| Name | Required | Description | Default |
|---|---|---|---|
| kind | Yes | 'asr', 'summary', or 'both'. | |
| text | No | Summary text. REQUIRED when kind='summary' or kind='both'. | |
| model | No | Optional — your model identifier, e.g. 'claude-opus-4'. | |
| title | No | Video title (for display). | |
| author | No | Channel/author name. | |
| format | No | Summary format: 'markdown' (default) or 'text'. Used with kind='summary' or kind='both'. Set 'markdown' if your text uses **bold**, bullets, headings, or code fences so the web UI renders it; set 'text' for plain prose. | |
| locale | No | Summary locale (e.g. en, zh). Used with kind='summary' or kind='both'. | |
| language | No | Video language code. | |
| video_id | Yes | YouTube video ID. | |
| thumbnail | No | Thumbnail URL. | |
| video_url | No | Full YouTube URL. | |
| visibility | No | 'public' to publish into the public Knowledge Base (searchable via search_kb), or 'private' (default). When set, applies to both new rows and existing ones — equivalent to PATCH /api/library/:id/visibility right after the save. |
Tool Definition Quality
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare idempotentHint=true and readOnlyHint=false. The description adds value by disclosing cost ('Costs one API call unit; no credits.') and behavioral constraints like ASR completion requirement for kind='asr'. No contradiction with annotations.
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 sufficiently concise with a front-loaded purpose. It packs significant detail about modes and cost into a compact structure. Every sentence adds value, though it could be slightly more streamlined.
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 11 parameters and no output schema, the description does not explain what the tool returns (e.g., success status, item details). It also lacks error conditions or prerequisites beyond ASR completion. For a mutation tool with no output schema, this is a notable gap.
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?
Schema coverage is 100%, so baseline is 3. The description adds helpful context for the 'format' parameter (explaining rendering of markdown vs. text) and mentions conditions for 'text' parameter (required for certain kinds). However, most parameter meanings are already clear from the schema descriptions.
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: 'Save a video to the user's Library' and details three distinct modes ('asr', 'summary', 'both') with specific use cases. This differentiates it from sibling tools like list_library and get_library_item, which are for retrieval.
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 explicit guidance on when to use each mode, including the recommendation to use 'both' when summarizing a recently transcribed video to save a round-trip and quota. It does not mention when not to use the tool or alternatives, but the mode-specific requirements offer clear context.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
search_channel_videosARead-onlyInspect
Search for specific videos within a YouTube channel. Use when the user wants to find a specific video from a known creator, e.g. 'find the video where @mkbhd talks about iPhone', 'did [creator] ever cover [topic]'. Costs 1 credit.
| Name | Required | Description | Default |
|---|---|---|---|
| q | Yes | Search query | |
| limit | No | Max results (1-50, default 30) | |
| channel | Yes | @handle, channel URL, or UC... ID |
Tool Definition Quality
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations declare readOnlyHint and destructiveHint, so no contradiction. Description adds behavioral info about cost ('Costs 1 credit'), which is useful beyond annotations.
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?
Two sentences with embedded examples, no wasted words. Front-loaded with purpose.
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?
For a simple search tool with no output schema, description covers purpose, usage, parameter details, and cost. Lacks return format info but that's acceptable without output schema.
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?
Schema coverage is 100%, so baseline is 3. Description adds extra meaning for channel parameter ('@handle, channel URL, or UC... ID') and provides query examples, adding value beyond schema.
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?
Description clearly states 'Search for specific videos within a YouTube channel' with specific verb and resource. Distinguishes from siblings like search_youtube and list_channel_videos via example queries and context.
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?
Provides explicit usage guidance with examples ('find the video where @mkbhd talks about iPhone'). Does not explicitly state when not to use, but the examples and sibling tool names imply alternatives.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
search_kbARead-onlyIdempotentInspect
Search the public Knowledge Base of community-shared video summaries. Use whenever the user asks about a topic, person, or concept that someone may have already summarized — this saves credits versus re-summarizing a video. Free; no API token quota.
| Name | Required | Description | Default |
|---|---|---|---|
| q | No | Search query — substring match on title/author/summary text. | |
| limit | No | Max items (1-100, default 20). | |
| offset | No | Pagination offset. |
Tool Definition Quality
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already indicate readOnlyHint=true and idempotentHint=true, so the description's safety profile is clear. The description adds useful context about substring matching, free cost, and no quota, but these supplement rather than significantly extend the behavioral understanding beyond annotations. No contradictions.
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 three concise sentences: purpose, usage guideline, and cost note. Information is front-loaded and each sentence adds value. Minor improvement could be merging the cost note into the usage sentence, but current structure is efficient.
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?
For a search tool with 3 optional parameters and no output schema, the description covers purpose, usage context, and cost. It does not mention pagination or output format, but given the low complexity and presence of annotations, it is sufficiently complete.
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?
Input schema has 100% coverage, so the description does not need to add parameter details. The description repeats the schema's 'substring match' but does not provide further semantic enrichment. Baseline score of 3 is appropriate as the schema already documents parameters adequately.
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 searches the 'public Knowledge Base of community-shared video summaries', using a specific verb and resource. It distinguishes from sibling search tools like search_youtube by specifying the KB scope. The additional note about being free and not using API quota further clarifies its unique purpose.
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 explicitly advises using this tool when the user asks about a topic that may have an existing summary, highlighting credit savings. It also notes it's free with no token quota. However, it does not mention when not to use it or list alternatives, slightly limiting guidance on exclusion.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
search_podcastARead-onlyInspect
Search podcasts (shows) or episodes from the open Podcast Index. Use when the user mentions a podcast, podcast host, audio show, or asks about a topic where podcast content adds value alongside video. type=podcast returns shows; type=episode returns recent episodes for the top-matching show and includes the RSS-declared transcript URL when the feed exposes one. Costs 1 credit.
| Name | Required | Description | Default |
|---|---|---|---|
| q | Yes | Search query — show name, host, or topic. | |
| type | No | podcast (shows) or episode (recent episodes of top show). Default: podcast. | |
| limit | No | Max results (1-50, default 20). |
Tool Definition Quality
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description adds behavioral details beyond annotations: it explains that type=episode returns recent episodes with the RSS-declared transcript URL when available, and mentions the cost. Annotations already indicate read-only and non-destructive, and the description is consistent.
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 concise with four focused sentences. Each sentence adds unique value: stating the function, providing usage context, detailing type behaviors, and noting credit cost. No redundant or unnecessary 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 no output schema, the description adequately explains return types for each type option and mentions transcript URLs. It covers usage context and cost. It lacks details on pagination or error handling, but for a search tool, it is reasonably complete.
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?
Input schema has 100% coverage, so baseline is 3. The description adds value by explaining the effect of the type parameter (podcast vs episode) and the transcript URL detail for episodes, going beyond the schema descriptions.
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 searches podcasts or episodes from the open Podcast Index, with specific verbs and resource. It distinguishes between type=podcast (shows) and type=episode (episodes), and provides usage context differentiating it from sibling tools like search_youtube.
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?
Explicitly states when to use this tool ('when the user mentions a podcast, podcast host, audio show, or asks about a topic where podcast content adds value alongside video'), explains the two type options, and mentions the cost of 1 credit, giving clear guidance on usage context.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
search_youtubeARead-onlyInspect
Search YouTube for videos, channels, or playlists on any topic. Use when the user wants to find videos, wants recommendations, is researching a topic that could benefit from video sources, wants to learn something that likely has YouTube tutorials, or when YouTube content would enhance your answer. Proactively search YouTube whenever video content adds value. Costs 1 credit.
| Name | Required | Description | Default |
|---|---|---|---|
| q | Yes | Search query | |
| type | No | Search type: video, channel, or playlist. Default: video. | |
| limit | No | Max results (1-50, default 20) |
Tool Definition Quality
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already indicate readOnlyHint=true and destructiveHint=false. The description adds the behavioral note 'Costs 1 credit' and encourages proactive use, but does not mention rate limits or output details. No contradiction with annotations.
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 three concise sentences, front-loaded with purpose, followed by usage guidance and a note on cost. No unnecessary words.
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 no output schema, the description does not explain the return format or pagination. It is adequate for a search tool but could be more complete about what results include.
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?
Schema description coverage is 100% with clear descriptions for each parameter. The description's mention of 'videos, channels, or playlists' aligns with the 'type' parameter but adds no new semantics beyond what the schema provides.
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 'Search YouTube for videos, channels, or playlists on any topic,' specifying the verb (search) and resource (YouTube) and listing the types of resources. It distinguishes from sibling tools like fetch_transcript or fetch_video_info.
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 explicit scenarios for use: 'when the user wants to find videos, wants recommendations...' and encourages proactive use. It also mentions the cost of 1 credit, giving clear guidance on when to invoke.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
transcribe_videoAIdempotentInspect
Start an AI transcription (Whisper) of a YouTube video. Use when the video has no captions, when fetch_transcript returned NO_CAPTIONS, or when the user explicitly wants an AI transcript. ASYNC — returns task_id + estimated_wait_seconds. Tell the user how long it will take, then call get_asr_task to check status. Do not poll faster than next_poll_after_seconds. Costs 5 credits on completion.
| Name | Required | Description | Default |
|---|---|---|---|
| lang | No | Optional language hint (e.g. en, zh). Omit to auto-detect. | |
| video_url | Yes | YouTube URL (watch, youtu.be, shorts, embed). |
Tool Definition Quality
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Transcends annotations by describing async nature, return of task_id and estimated_wait_seconds, and credit cost (5 credits on completion). Polling guidelines are clear. No contradictions with annotations.
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?
Three concise sentences: purpose/usage, async behavior/user instruction, polling/cost. Every sentence adds value, no redundancy, front-loaded.
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?
Covers key aspects: when to use, async return, polling, cost. Lacks explicit error handling or credit deduction timing, but sufficient for common scenarios. Output schema absent but description mentions return fields.
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?
Input schema has 100% coverage with descriptions. Description adds minimal extra context (e.g., URL formats, language hint example). Baseline 3 is appropriate as schema already covers parameters.
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 action ('Start an AI transcription') and the resource ('a YouTube video'). It differentiates from sibling 'fetch_transcript' by specifying when to use: when no captions exist or explicitly requested.
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?
Explicit usage conditions are provided: use when no captions, fetch_transcript returned NO_CAPTIONS, or explicit user request. It also instructs on async behavior, polling via get_asr_task, and not to poll faster than specified. Alternative (fetch_transcript) is implied.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Claim this connector by publishing a /.well-known/glama.json file on your server's domain with the following structure:
{
"$schema": "https://glama.ai/mcp/schemas/connector.json",
"maintainers": [{ "email": "your-email@example.com" }]
}The email address must match the email associated with your Glama account. Once published, Glama will automatically detect and verify the file within a few minutes.
Control your server's listing on Glama, including description and metadata
Access analytics and receive server usage reports
Get monitoring and health status updates for your server
Feature your server to boost visibility and reach more users
For users:
Full audit trail – every tool call is logged with inputs and outputs for compliance and debugging
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Change alerts – get notified when a connector changes its schema, adds or removes tools, or updates tool definitions, so nothing breaks silently
For server owners:
Proven adoption – public usage metrics on your listing show real-world traction and build trust with prospective users
Tool-level analytics – see which tools are being used most, helping you prioritize development and documentation
Direct user feedback – users can report issues and suggest improvements through the listing, giving you a channel you would not have otherwise
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If you are the owner of this MCP connector and would like to make modifications to the listing, including providing test credentials for accessing the server, please contact support@glama.ai.
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