Server Quality Checklist

Tool Scores

• channels_getChannelB
  3.3/5.0
  Behavior3/5

  Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

  Annotations already declare readOnlyHint=true and idempotentHint=true, so the agent knows this is a safe, repeatable read operation. The description adds no behavioral context beyond this, such as rate limits, authentication requirements, or error handling. With annotations covering key traits, a baseline 3 is appropriate, but the description misses opportunities to enhance transparency.

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness5/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  The description is a single, efficient sentence that directly states the tool's purpose without redundancy. It's front-loaded with essential information and wastes no words, making it easy for an agent to parse quickly. This exemplifies optimal conciseness for a simple tool.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness3/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  For a read-only, idempotent tool with one well-documented parameter and no output schema, the description is minimally complete. It covers the basic action but lacks details on return values, error cases, or integration with sibling tools. While annotations help, the description doesn't fully compensate for the missing output schema, leaving gaps in contextual understanding.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters3/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  Schema description coverage is 100%, with the single parameter 'channelId' fully documented in the schema. The description adds no additional meaning about the parameter, such as format examples (e.g., 'UC...') or sourcing tips. Given high schema coverage, the baseline score of 3 reflects adequate but minimal value from the description.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose4/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  The description clearly states the verb 'Get' and the resource 'information about a YouTube channel', making the purpose immediately understandable. It distinguishes from siblings like 'channels_listVideos' by focusing on channel metadata rather than video listings. However, it doesn't specify what information is retrieved (e.g., statistics, description, thumbnails), keeping it from a perfect score.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines2/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., authentication), differentiate from similar tools like 'videos_getVideo' for video-specific data, or indicate scenarios where channel information is needed over other operations. This leaves the agent without context for tool selection.

  Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

• channels_listVideosB
  3.3/5.0
  Behavior3/5

  Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

  Annotations declare readOnlyHint=true and idempotentHint=true, so the agent knows this is a safe, repeatable read operation. The description adds no behavioral context beyond what annotations provide—it doesn't mention pagination behavior, rate limits, authentication requirements, or what the return format looks like. However, it doesn't contradict annotations, so it meets the lower bar with annotations present but adds minimal value.

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness5/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  The description is a single, efficient sentence with zero waste—'Get videos from a specific channel' directly conveys the core action without fluff. It's appropriately sized for a simple list operation and front-loaded with the essential information. Every word earns its place.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness3/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  Given the tool's low complexity (simple list operation), rich annotations (readOnlyHint, idempotentHint), and 100% schema coverage, the description is minimally adequate. However, with no output schema, the description doesn't explain return values (e.g., video list format, metadata included), which is a gap. It's complete enough for basic use but lacks details on output behavior.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters3/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  Schema description coverage is 100%, with both parameters ('channelId' and 'maxResults') fully described in the schema. The description adds no parameter semantics beyond what the schema provides—it doesn't explain format expectations for 'channelId' (e.g., YouTube-specific ID format) or default/typical values for 'maxResults'. Baseline 3 is appropriate since the schema does the heavy lifting.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose4/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  The description 'Get videos from a specific channel' clearly states the verb 'Get' and resource 'videos' with scope 'from a specific channel'. It distinguishes from siblings like 'videos_getVideo' (single video) and 'videos_searchVideos' (search across YouTube), but doesn't explicitly differentiate from all siblings like 'playlists_getPlaylistItems' which also retrieves video lists. The purpose is specific but could be more precise about the list nature.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines2/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  The description provides no guidance on when to use this tool versus alternatives. It doesn't mention when to choose this over 'videos_searchVideos' for channel-specific searches, or 'playlists_getPlaylistItems' for playlist videos. There's no context about prerequisites (e.g., authentication needs) or exclusions. Usage is implied by the name but not explicitly stated.

  Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

• playlists_addVideoB
  3.3/5.0
  Behavior3/5

  Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

  Annotations indicate this is a non-read-only and non-idempotent operation, which the description does not contradict. The description adds value by specifying the OAuth authentication requirement, which is not covered by annotations. However, it lacks details on behavioral aspects like error handling, rate limits, or side effects beyond authentication.

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness5/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  The description is a single, efficient sentence that front-loads the core purpose and includes essential authentication information. There is no wasted verbiage, and every word contributes to understanding the tool's function and requirements.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness3/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  Given the tool's moderate complexity (mutation with authentication) and lack of an output schema, the description is minimally adequate. It covers the basic purpose and authentication need but omits details on return values, error conditions, or interaction with sibling tools, leaving gaps in contextual understanding.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters3/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  Schema description coverage is 100%, meaning all parameters are documented in the schema. The description does not add any semantic details beyond what the schema provides, such as explaining the implications of the 'position' parameter or format requirements for IDs. Baseline score of 3 is appropriate as the schema handles parameter documentation adequately.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose4/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  The description clearly states the action ('Add a video') and resource ('to a YouTube playlist'), which is specific and unambiguous. However, it does not explicitly differentiate from its sibling 'playlists_addVideos' (which likely adds multiple videos), leaving some room for improvement in sibling distinction.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines2/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  The description mentions that OAuth authentication is required, which provides some context for usage prerequisites. However, it offers no guidance on when to use this tool versus alternatives like 'playlists_addVideos' or 'playlists_create', nor does it specify any exclusions or scenarios where this tool is preferred.

  Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

• playlists_addVideosB
  3.3/5.0
  Behavior3/5

  Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

  Annotations indicate this is not read-only and not idempotent, which the description doesn't contradict. The description adds value by specifying the OAuth requirement, which isn't covered by annotations. However, it lacks details on rate limits, error handling, or what happens on partial failures (e.g., if some video IDs are invalid).

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness5/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  The description is a single, efficient sentence that front-loads the core purpose and includes the key constraint (OAuth). There's no wasted verbiage, and every word contributes to understanding the tool's function and requirements.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness3/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  Given the mutation nature (annotations show not read-only), lack of output schema, and 2 required parameters, the description is minimally adequate. It covers authentication but misses behavioral aspects like response format or error scenarios. With annotations providing some safety context, it's passable but could be more complete for a write operation.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters3/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  Schema description coverage is 100%, with clear parameter descriptions in the schema. The description doesn't add any semantic details beyond what's in the schema (e.g., format of IDs, constraints on array size). Baseline 3 is appropriate since the schema fully documents parameters.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose4/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  The description clearly states the action ('Add multiple videos') and resource ('to a YouTube playlist'), which is specific and actionable. However, it doesn't explicitly differentiate from its sibling 'playlists_addVideo', which appears to be a single-video version, though the 'multiple' distinction is implied.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines2/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  The description mentions OAuth authentication as a requirement, which provides some context, but it doesn't offer guidance on when to use this tool versus alternatives like 'playlists_addVideo' or 'playlists_create'. No explicit when-not-to-use or prerequisite information is included.

  Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

• playlists_createB
  3.3/5.0
  Behavior3/5

  Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

  Annotations already declare readOnlyHint=false and idempotentHint=false, correctly indicating this is a non-idempotent write operation. The description adds the OAuth authentication requirement, which is valuable context beyond annotations. However, it doesn't describe other behavioral aspects like rate limits, error conditions, or what happens on duplicate playlist creation attempts. The description complements but doesn't fully compensate for the lack of output schema.

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness5/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  The description is a single, efficient sentence that communicates the core action and key constraint. Every word earns its place - 'Create' (action), 'new YouTube playlist' (resource), and 'requires OAuth authentication' (critical constraint). No wasted words or unnecessary elaboration. Perfectly front-loaded with essential information.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness3/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  For a creation tool with 3 parameters, 100% schema coverage, and annotations covering read/write/idempotency, the description provides the minimum viable information. The OAuth requirement is important context, but without an output schema, the description doesn't explain what gets returned (playlist ID, success confirmation, etc.). It's adequate but leaves gaps about the creation result and error handling.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters3/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  Schema description coverage is 100%, with all parameters well-documented in the schema itself. The description adds no parameter-specific information beyond what's already in the schema. According to scoring rules, when schema_description_coverage is high (>80%), the baseline is 3 even with no param info in description. The description doesn't compensate but doesn't need to given the comprehensive schema.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose4/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  The description clearly states the verb 'Create' and resource 'new YouTube playlist', making the purpose unambiguous. It distinguishes from siblings like playlists_getPlaylist (read) and playlists_addVideo (modify), but doesn't explicitly contrast with all sibling tools. The description is specific but could be more precise about differentiation.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines2/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  The description mentions 'requires OAuth authentication' which provides some context about prerequisites, but offers no guidance on when to use this tool versus alternatives. It doesn't indicate when to create a playlist versus using existing ones, or how it relates to sibling tools like playlists_addVideo for modifying playlists. No explicit when/when-not statements or alternative recommendations are provided.

  Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

• playlists_getPlaylistB
  3.3/5.0
  Behavior3/5

  Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

  Annotations already declare readOnlyHint=true and idempotentHint=true, so the agent knows this is a safe, repeatable read operation. The description adds no behavioral context beyond this, such as rate limits, authentication needs, or what specific information is returned, but it doesn't contradict the annotations.

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness5/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  The description is a single, efficient sentence with zero waste, front-loaded with the core action. It's appropriately sized for a simple tool, making it easy to parse quickly.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness3/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  Given the tool's low complexity (1 parameter, no output schema) and rich annotations (readOnlyHint, idempotentHint), the description is minimally adequate. However, it lacks details on return values or error handling, which could be helpful despite the annotations covering safety.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters3/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  Schema description coverage is 100%, with the single parameter 'playlistId' fully documented in the schema. The description adds no meaning beyond what the schema provides, such as format examples or constraints, so it meets the baseline for high coverage.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose4/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  The description clearly states the verb 'Get' and resource 'information about a YouTube playlist', making the purpose specific and understandable. However, it doesn't differentiate from sibling tools like 'playlists_getPlaylistItems' or 'videos_getVideo', which also retrieve information but for different resources, so it misses full sibling distinction.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines2/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  The description provides no guidance on when to use this tool versus alternatives. With siblings like 'playlists_getPlaylistItems' (for playlist items) and 'videos_getVideo' (for video details), there's no indication of context, prerequisites, or exclusions, leaving usage unclear.

  Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

• playlists_getPlaylistItemsB
  3.3/5.0
  Behavior3/5

  Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

  Annotations already indicate read-only and idempotent operations, so the agent knows this is a safe, repeatable read. The description adds minimal behavioral context beyond this, such as specifying it retrieves 'videos' (not other items) but doesn't detail pagination, rate limits, or response format. With annotations covering core safety, a baseline 3 is appropriate for the limited added value.

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness5/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  The description is a single, efficient sentence that directly states the tool's function without unnecessary words. It's front-loaded with the core action and resource, making it easy to parse quickly.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness3/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  Given the tool's low complexity (simple read operation), 100% schema coverage, and annotations providing safety hints, the description is adequate but minimal. It lacks output details (no output schema) and doesn't address sibling tool differentiation, which could help in more complex scenarios. A score of 3 reflects a basic but sufficient level of completeness for this context.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters3/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  Schema description coverage is 100%, with clear documentation for both parameters (playlistId and maxResults). The description doesn't add any semantic details beyond what the schema provides, such as examples of playlist IDs or default values for maxResults. Baseline 3 is correct when the schema fully documents parameters.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose4/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  The description clearly states the action ('Get') and resource ('videos in a YouTube playlist'), making the purpose immediately understandable. However, it doesn't explicitly differentiate from sibling tools like 'playlists_getPlaylist' (which likely gets playlist metadata) or 'channels_listVideos' (which might list videos from a channel rather than a playlist), missing full sibling distinction.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines2/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  The description provides no guidance on when to use this tool versus alternatives. It doesn't mention when to choose this over 'playlists_getPlaylist' for items vs. metadata, or 'channels_listVideos' for channel-based video listings, leaving usage context implied rather than explicit.

  Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

• transcripts_getTranscriptB
  3.3/5.0
  Behavior3/5

  Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

  Annotations already declare readOnlyHint=true and idempotentHint=true, so the agent knows this is a safe, repeatable read operation. The description adds no behavioral context beyond this, such as rate limits, authentication requirements, or transcript availability constraints, but doesn't contradict annotations.

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness5/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  The description is a single, direct sentence with zero wasted words, front-loading the core purpose efficiently. It's appropriately sized for a simple retrieval tool.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness3/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  Given the tool's low complexity, rich annotations (readOnlyHint, idempotentHint), and 100% schema coverage, the description is minimally adequate. However, without an output schema, it doesn't explain return values (e.g., transcript format), and it lacks context like authentication needs, leaving gaps for a complete understanding.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters3/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  Schema description coverage is 100%, with clear parameter descriptions in the schema. The description mentions 'transcript of a YouTube video', which implies the 'videoId' parameter but adds no semantic details beyond what the schema provides, such as format examples or language code specifics.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose4/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  The description clearly states the action ('Get') and resource ('transcript of a YouTube video'), making the purpose immediately understandable. However, it doesn't differentiate from sibling tools like 'videos_getVideo' or 'videos_getComments', which also retrieve YouTube content but different types, so it lacks sibling distinction.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines2/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., authentication needs), exclusions, or compare to siblings like 'videos_getVideo' for general video info, leaving the agent to infer usage context.

  Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

• videos_getVideoB
  3.3/5.0
  Behavior3/5

  Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

  Annotations already indicate read-only and idempotent behavior, so the description does not need to repeat these traits. It adds minimal context by specifying the type of information retrieved ('detailed information about a YouTube video including URL'), but does not disclose additional behavioral aspects like rate limits, error conditions, or response format.

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness5/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  The description is a single, efficient sentence that directly states the tool's purpose without unnecessary words. It is front-loaded with the core functionality, making it easy for an agent to quickly understand the tool's intent.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness3/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  Given the tool's low complexity (2 parameters, no output schema) and rich annotations (read-only, idempotent), the description is adequate but basic. It covers the purpose but lacks details on usage context, output structure, or error handling, which could enhance agent understanding despite the annotations.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters3/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  Schema description coverage is 100%, so the schema fully documents both parameters ('videoId' and 'parts'). The description does not add any semantic details beyond what the schema provides, such as examples of valid 'parts' values or URL format specifics, meeting the baseline for high schema coverage.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose4/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  The description clearly states the tool's purpose: 'Get detailed information about a YouTube video including URL'. It specifies the verb ('Get'), resource ('YouTube video'), and scope ('detailed information'), but does not explicitly distinguish it from sibling tools like 'videos_getComments' or 'videos_searchVideos', which also retrieve video-related data.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines2/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  The description provides no guidance on when to use this tool versus alternatives. It does not mention sibling tools such as 'videos_searchVideos' for finding videos or 'videos_getComments' for retrieving comments, leaving the agent without context for tool selection.

  Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

• videos_searchVideosB
  3.3/5.0
  Behavior3/5

  Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

  Annotations indicate read-only and idempotent operations, which the description does not contradict. The description adds minimal behavioral context by specifying the return includes 'URLs', but it lacks details on rate limits, authentication needs, or result formatting. With annotations covering safety, this is adequate but not rich.

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness5/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  The description is a single, efficient sentence that directly states the tool's purpose and output without unnecessary details. It is front-loaded and wastes no words, making it highly concise and well-structured.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness3/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  Given the tool's low complexity, two parameters with full schema coverage, and annotations providing safety hints, the description is minimally complete. However, without an output schema, it could benefit from more detail on result structure or limitations, but it meets basic requirements for a search tool.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters3/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  Schema description coverage is 100%, so parameters are fully documented in the schema. The description does not add meaning beyond the schema, such as explaining query syntax or default values for 'maxResults'. Baseline score of 3 is appropriate as the schema carries the burden.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose4/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  The description clearly states the action ('Search for videos') and resource ('on YouTube'), and specifies what is returned ('results with URLs'). However, it does not explicitly differentiate from sibling tools like 'channels_listVideos' or 'videos_getVideo', which reduces clarity in distinguishing use cases.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines2/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  The description provides no guidance on when to use this tool versus alternatives, such as 'channels_listVideos' for videos from a specific channel or 'videos_getVideo' for details on a single video. It lacks context on prerequisites, exclusions, or recommended scenarios, offering only a basic functional statement.

  Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

• videos_getCommentsA
  3.8/5.0
  Behavior4/5

  Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

  Annotations already declare readOnlyHint=true and idempotentHint=true, indicating a safe, repeatable read operation. The description adds value by specifying 'with pagination support,' which clarifies behavioral traits beyond annotations (e.g., handling large datasets via pageToken). It doesn't detail rate limits or auth needs, but this is acceptable given the annotations cover core safety.

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness5/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  The description is a single, efficient sentence that front-loads the core purpose ('Get comments from a YouTube video') and adds key behavioral context ('with pagination support'). Every word earns its place, with no redundancy or fluff, making it appropriately sized and well-structured.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness4/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  Given the tool's moderate complexity (4 parameters, 1 required), rich annotations (readOnlyHint, idempotentHint), and 100% schema coverage, the description is reasonably complete. It lacks an output schema, but the description doesn't need to explain return values. It could benefit from more usage context, but overall it's adequate for the tool's profile.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters3/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  Schema description coverage is 100%, with each parameter well-documented in the schema (e.g., videoId, maxResults with limits, order with enum, pageToken). The description adds no additional parameter semantics beyond what's in the schema, so it meets the baseline of 3 for high coverage without extra value.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose4/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  The description clearly states the action ('Get comments') and resource ('from a YouTube video'), distinguishing it from sibling tools like videos_getVideo or transcripts_getTranscript. However, it doesn't explicitly differentiate from other comment-related tools (though none are listed among siblings), making it clear but not fully sibling-differentiated.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines3/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  The description implies usage for retrieving comments from a specific video, but provides no explicit guidance on when to use this tool versus alternatives (e.g., for searching videos or getting channel info). It mentions pagination support, which hints at use for large datasets, but lacks clear when/when-not instructions or named alternatives.

  Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

• youtube_getAuthUrlA
  3.9/5.0
  Behavior4/5

  Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

  Annotations indicate readOnlyHint=true and idempotentHint=true, which the description doesn't contradict. The description adds valuable context beyond annotations by explaining that the URL is for user authorization, clarifying the tool's role in the OAuth process. However, it doesn't detail behavioral aspects like rate limits or error handling, keeping it from a perfect score.

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness5/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  The description is highly concise and front-loaded: two sentences that directly state the tool's function and its purpose in the authorization flow. Every sentence earns its place with no wasted words, making it easy to understand quickly.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness4/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  Given the tool's low complexity (0 parameters, no output schema) and rich annotations (readOnlyHint, idempotentHint), the description is mostly complete. It explains what the tool does and its role in OAuth, but could benefit from mentioning the relationship to sibling auth tools or what happens after authorization for better context.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters4/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  The input schema has no parameters (parameter count: 0), with 100% schema description coverage. The description doesn't add parameter details, which is unnecessary here. A baseline of 4 is appropriate as the schema fully covers the lack of parameters, and the description doesn't need to compensate.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose4/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  The description clearly states the tool's purpose: 'Get the OAuth authorization URL' specifies the verb (get) and resource (URL), and 'User needs to visit this URL to authorize the app' explains its role in the OAuth flow. However, it doesn't explicitly differentiate from sibling tools like 'youtube_checkAuth' or 'youtube_startAuth', which appear related to authentication but have different functions.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines3/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  The description implies usage context by stating 'User needs to visit this URL to authorize the app', suggesting this tool is for initiating OAuth authorization. However, it lacks explicit guidance on when to use this versus alternatives like 'youtube_startAuth' or 'youtube_checkAuth', and doesn't specify prerequisites or exclusions, leaving some ambiguity.

  Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

• youtube_startAuthA
  3.9/5.0
  Behavior4/5

  Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

  Annotations indicate readOnlyHint=false and idempotentHint=false, but the description adds valuable behavioral context: it specifies that the tool opens a local server and waits for a callback, which reveals implementation details and interactive behavior not covered by annotations. This helps the agent understand this is a blocking, interactive operation with side effects.

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness5/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  The description is two concise sentences that efficiently convey the core action and key behavioral detail. Every word earns its place with no redundancy or fluff, making it easy to parse and front-loaded with essential information.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness4/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  Given the tool's complexity (OAuth flow initiation), annotations cover safety hints, but no output schema exists. The description provides enough context about the interactive nature (local server, callback waiting) to guide usage, though it could benefit from mentioning typical next steps or error handling. It's reasonably complete for a 0-parameter tool with behavioral annotations.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters4/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  With 0 parameters and 100% schema description coverage, the baseline is 4. The description doesn't need to explain parameters, and it doesn't add any parameter-specific information, which is appropriate given the empty schema.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose4/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  The description clearly states the tool's purpose: 'Start OAuth authentication flow' specifies the verb (start) and resource (OAuth flow). It distinguishes from siblings like youtube_checkAuth and youtube_getAuthUrl by focusing on initiating the flow rather than checking status or getting URLs. However, it doesn't explicitly differentiate from all authentication-related siblings.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines3/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  The description implies usage context by mentioning 'Opens a local server and waits for callback,' suggesting this is for initiating authentication when no existing session exists. However, it doesn't explicitly state when to use this vs. alternatives like youtube_checkAuth (to verify existing auth) or youtube_getAuthUrl (to get URL without starting flow), nor does it mention prerequisites or exclusions.

  Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

• youtube_checkAuthA
  4.2/5.0
  Behavior3/5

  Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

  Annotations already declare readOnlyHint=true and idempotentHint=true, indicating a safe, repeatable read operation. The description adds value by clarifying that it checks for OAuth configuration and credentials specifically for write operations, which provides context beyond the annotations. No contradictions exist.

  Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

  Conciseness5/5

  Is the description appropriately sized, front-loaded, and free of redundancy?

  The description is a single, efficient sentence that directly states the tool's purpose without unnecessary words. It is front-loaded with the core action ('Check if OAuth is configured') and includes essential context ('for write operations'), making it highly concise and well-structured.

  Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

  Completeness4/5

  Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

  Given the tool's simplicity (0 parameters, no output schema) and rich annotations, the description is complete enough for an AI agent to understand when and how to use it. It could slightly improve by specifying the return format or error conditions, but it adequately covers the tool's role in the context of sibling authentication tools.

  Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

  Parameters4/5

  Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

  With 0 parameters and 100% schema description coverage, the schema fully documents the input structure. The description appropriately does not add parameter details, as none are needed, and instead focuses on the tool's functional intent, which is sufficient for this case.

  Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

  Purpose5/5

  Does the description clearly state what the tool does and how it differs from similar tools?

  The description clearly states the tool's purpose with specific verbs ('Check if OAuth is configured' and 'we have valid credentials') and identifies the resource ('write operations'). It distinguishes itself from sibling tools like 'youtube_getAuthUrl' and 'youtube_startAuth' by focusing on verification rather than authentication initiation.

  Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

  Usage Guidelines4/5

  Does the description explain when to use this tool, when not to, or what alternatives exist?

  The description implies usage context by specifying 'for write operations,' suggesting this tool should be used before attempting write actions. However, it does not explicitly state when not to use it or name alternatives, such as checking authentication status separately from other tools.

  Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.