Spotify MCP Server

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

No annotations are provided, so the description bears full responsibility for behavioral disclosure. It states the action ('adds') but does not clarify whether items are appended to the queue, whether an active device is required, what occurs if the item is unavailable, or any side effects. This lack of detail is a significant gap for a mutation tool.

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

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

The description is a single concise sentence that front-loads the verb and resource. Every word contributes meaning; there is zero waste or repetition.

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, the description is adequate for basic understanding. However, with no output schema or annotations, it lacks important operational context such as prerequisites (active device), whether the operation replaces or appends to the queue, and error behavior. This leaves room for ambiguity in real-world usage.

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

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

The schema provides complete descriptions for all four parameters (100% coverage), so the baseline is 3. The description adds no extra semantics beyond referencing the item types, which aligns with the 'type' enum. It does not clarify the relationship between id, uri, and type, but the schema already handles that 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 uses a specific verb 'Adds' and identifies the exact resource 'playback queue', while also enumerating the accepted item types (track, album, artist, playlist). This clearly distinguishes it from sibling tools like addTracksToPlaylist (which targets a playlist) and playMusic (which initiates playback).

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 implies the use case: when you want to place an item into the playback queue rather than playing it immediately or adding to a playlist. However, it does not explicitly state when to prefer this tool over siblings like playMusic or addTracksToPlaylist, nor does it mention any prerequisites such as an active device.

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

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. The text merely paraphrases the tool name without revealing side effects, authentication requirements, or post-conditions (e.g., whether tracks are appended or replaced). It does not add value beyond what the name already implies.

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

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

The description is a single sentence with no filler or redundant text. It is front-loaded with the core action, making it efficient and easy to parse for an AI agent.

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?

This is a mutation tool with no annotations, no output schema, and a minimal description. It fails to communicate important contextual details such as whether the operation is idempotent, duplicate handling, limits on track count, or required permissions. The description is under-specified for reliable 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 description coverage is 100%, with each parameter (playlistId, trackIds, position) having a clear description. The tool description adds nothing extra about parameter usage, but the schema already provides sufficient meaning, so the baseline of 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?

The description clearly states the tool's action ('Add tracks') and resource ('a Spotify playlist'), using a specific verb+resource structure. It is distinct from sibling tools like addToQueue or createPlaylist, which target different operations.

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

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

No guidance is provided on when to use this tool versus alternatives such as addToQueue or createPlaylist. The description lacks any context about prerequisites, sequencing, or preferred scenarios, offering zero actionable usage advice.

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

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool checks saved albums but doesn't reveal key behaviors such as authentication requirements, rate limits, response format, or error handling. For a read operation with zero annotation coverage, this is a significant gap in transparency.

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

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

The description is a single, efficient sentence that directly states the tool's purpose without any wasted words. It's front-loaded and appropriately sized for its function, making it easy for an agent to parse quickly.

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 lack of annotations and output schema, the description is incomplete. It doesn't cover behavioral aspects like authentication, rate limits, or response format, which are crucial for a tool interacting with a user's library. For a tool with no structured metadata, more context is needed to be fully helpful.

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

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

The description doesn't add any parameter semantics beyond what the input schema provides. Since schema description coverage is 100%, the schema already fully documents the 'albumIds' parameter (array of Spotify album IDs, max 20). The baseline score of 3 is appropriate as the description doesn't compensate but the schema handles the documentation 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 action ('Check if albums are saved') and the resource ('user's "Your Music" library'), making the purpose immediately understandable. However, it doesn't explicitly distinguish this tool from sibling tools like 'getUsersSavedTracks' or 'saveOrRemoveAlbumForUser', which would require more specific differentiation to earn a 5.

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 no guidance on when to use this tool versus alternatives. It doesn't mention sibling tools like 'getUsersSavedTracks' (which retrieves saved tracks) or 'saveOrRemoveAlbumForUser' (which modifies saved albums), nor does it specify prerequisites or contexts for use, leaving the agent without usage direction.

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

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

With no annotations, the description is the sole source of behavioral information. It only says 'Create a new playlist', which implies mutation but does not disclose side effects, permission requirements, or behavior on duplicate names. No additional context is provided.

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

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

The description is a single, direct sentence that immediately conveys the tool's function. It is appropriately sized and front-loaded, containing no unnecessary words or repetitions.

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 create operation with fully documented parameters, the description is minimally adequate. However, it lacks any reference to return values or usage context, and the absence of an output schema increases the burden on the description to explain the outcome.

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

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

The input schema provides 100% coverage for all three parameters (name, public, description) with clear descriptions. The tool description adds no extra semantic value beyond the schema, so it earns the baseline score.

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 ('Create') and the resource ('a new playlist on Spotify'), which distinguishes it from sibling tools like updatePlaylist. However, it does not enumerate the configurable fields, so it's not as detailed as it could be.

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 no explicit guidance on when to use this tool versus alternatives such as updatePlaylist or addTracksToPlaylist. It also omits any prerequisites or exclusions, leaving the usage context entirely implicit.

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

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states it 'gets detailed information' but doesn't specify what details are included (e.g., artist, release date, tracks), whether it requires authentication, rate limits, or error handling. This leaves significant gaps for a tool with no annotation coverage.

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

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

The description is a single, efficient sentence that directly states the tool's purpose without unnecessary words. It's appropriately sized and front-loaded, making it easy to parse quickly.

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 annotations and no output schema, the description is incomplete for a tool that likely returns complex album data. It doesn't explain what 'detailed information' includes, response format, or error cases, leaving the agent with insufficient context to use the tool effectively.

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 the schema fully documenting the 'albumIds' parameter as a single ID or array (max 20). The description adds minimal value beyond this by mentioning 'one or more albums by their Spotify IDs', which aligns with but doesn't expand on the schema. Baseline 3 is appropriate when the schema does the heavy lifting.

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 verb ('Get detailed information') and resource ('about one or more albums by their Spotify IDs'), making the purpose specific and understandable. However, it doesn't explicitly differentiate from sibling tools like 'getAlbumTracks' or 'checkUsersSavedAlbums', which prevents 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.

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 use 'getAlbums' over 'getAlbumTracks' (which retrieves tracks within albums) or 'checkUsersSavedAlbums' (which checks user's saved status), nor does it specify prerequisites or exclusions.

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

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions 'pagination support', which is useful, but lacks details on permissions, rate limits, error handling, or response format. For a read operation with no annotation coverage, this leaves significant gaps in understanding how the tool behaves.

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

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

The description is a single, efficient sentence that directly states the tool's function and key feature (pagination). It is front-loaded with the core purpose and avoids any unnecessary 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.

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

Given the complexity of a read operation with pagination, no annotations, and no output schema, the description is incomplete. It doesn't explain what the return values look like (e.g., track list format), error conditions, or authentication needs, leaving the agent with insufficient context for reliable use.

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

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

The input schema has 100% description coverage, clearly documenting all parameters (albumId, limit, offset). The description adds no additional meaning beyond what the schema provides, such as examples or edge cases, so it meets the baseline for high schema coverage without enhancing parameter understanding.

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 verb ('Get') and resource ('tracks from a specific album'), making the purpose understandable. However, it doesn't explicitly differentiate from sibling tools like 'getAlbums' or 'getPlaylistTracks', which also retrieve music content, 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.

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. For example, it doesn't mention when to choose this over 'getAlbums' for album details or 'searchSpotify' for broader track searches, leaving the agent without contextual usage cues.

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

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

No annotations are present, so the description must explain behavior. It only states 'current user's playlists' but omits pagination limits, required scopes, and response structure.

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

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

The description is a single, straightforward sentence that delivers the core purpose without any extraneous words. It is appropriately sized for a simple tool.

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?

The tool has no output schema and no annotations, leaving the description as the sole context. It fails to mention that the result is an array of playlist objects or how the limit parameter affects paging, making it insufficient for agents needing detailed context.

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

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

The schema provides full documentation for the single 'limit' parameter, including type, min, max, and description. Since the schema coverage is 100%, the description does not need to add parameter details, and it adds none, so a 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 clearly specifies the verb 'Get', the resource 'list of playlists', and the scope 'current user's', which distinguishes it from sibling tools like getPlaylist (singular). It unambiguously states what the tool does.

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

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

No usage guidance is provided. The description does not mention alternatives or when to choose this over getPlaylist, so an agent receives no selection criteria.

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

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

With no annotations provided, the description carries the burden of behavioral disclosure. It implies a read-only operation via 'Get', but does not explicitly state that it has no side effects, requires active playback, or what happens if nothing is playing. The description adds minimal behavioral context beyond the tool's basic function.

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

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

The description is a single, concise sentence that conveys the essential purpose without any fluff or redundancy. Every word earns its place, and the information density is high.

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?

The tool is simple (no parameters, no output schema), but the description is somewhat thin. It does not specify what 'information' is returned (e.g., track name, artist, album) or address edge cases like no active playback. For a simple read tool, this is moderately complete but leaves room for ambiguity.

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

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

The input schema has zero parameters, and the description correctly avoids inventing any. With no parameters, the schema coverage is effectively 100%, and the baseline of 4 applies. The description does not need to add parameter-level detail.

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 verb 'Get' and the resource 'currently playing track on Spotify', which directly and unambiguously describes the tool's purpose. It is distinct from sibling tools like getRecentlyPlayed or searchSpotify, as it specifically targets the current playback state.

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 phrase 'currently playing' provides clear context that this tool is for retrieving live playback information, implicitly distinguishing it from search or playlist retrieval. However, it does not explicitly mention when not to use it or reference alternative tools, falling short of a full 5.

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

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

With no annotations, the description carries the full burden of behavioral disclosure. It only says 'Get a list of tracks' without explaining pagination (offset/limit), return structure, whether tracks are full objects or references, authentication needs, or error behavior. This is a minimal read operation but lacks important context.

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

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

The description is a single, concise sentence with no redundant words. It is front-loaded and gets straight to the point. This is appropriately sized for the simplicity of the tool.

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?

There is no output schema and no annotations. The description fails to explain what a 'list of tracks' actually contains (e.g., track metadata, audio features) or how pagination works. This is insufficient for a tool that has no other documentation beyond the 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 the baseline is 3. The description adds no parameter-specific meaning beyond what the schema already provides; all parameters are documented in the input schema with 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 action ('Get') and the resource ('a list of tracks in a Spotify playlist'), which distinguishes it from siblings like getAlbumTracks or getPlaylist. The verb+resource structure is specific and unambiguous.

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

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

No guidance is provided on when to use this tool versus alternatives such as getAlbumTracks or getUsersSavedTracks. The description only states what it does, leaving the agent to infer usage context. There are no exclusions or alternative mentions.

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

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool retrieves a list but doesn't describe key behaviors: whether it requires authentication, if it works only with an active playback session, potential rate limits, error conditions (e.g., no queue available), or the format of the returned list (e.g., JSON structure). This leaves significant gaps in understanding how the tool behaves in practice.

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

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

The description is a single, well-structured sentence that efficiently conveys the core functionality: 'Get a list of the currently playing track and the next items in your Spotify queue.' It is front-loaded with the main action and resource, with no unnecessary words or redundant information, making it highly concise and easy to understand at a glance.

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 moderate complexity (retrieving a dynamic queue with one optional parameter), lack of annotations, and no output schema, the description is incomplete. It doesn't cover behavioral aspects like authentication needs, session dependencies, error handling, or return format details. While the schema handles the parameter well, the overall context for safe and effective use is insufficient, especially for a tool that likely interacts with user-specific Spotify data.

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

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

The input schema has 100% description coverage, with the 'limit' parameter fully documented in the schema (type, range, and description). The tool description doesn't add any parameter-specific information beyond what the schema provides, such as default values or usage examples. Since schema coverage is high, the baseline score of 3 is appropriate, as the description doesn't compensate but also doesn't detract from the schema's documentation.

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: 'Get a list of the currently playing track and the next items in your Spotify queue.' It specifies the verb ('Get') and resource ('currently playing track and the next items in your Spotify queue'), making the action clear. However, it doesn't explicitly distinguish this tool from sibling tools like 'getNowPlaying' (which might only show the current track) or 'getRecentlyPlayed' (which shows past tracks), leaving some ambiguity in sibling differentiation.

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 no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an active Spotify session), exclusions (e.g., not applicable if no music is playing), or comparisons to siblings like 'getNowPlaying' (for current track only) or 'getRecentlyPlayed' (for past tracks). Without such context, users might struggle to choose the right tool in different scenarios.

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

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

With no annotations provided, the description must disclose behavioral traits, but it only states 'Get a list' without covering authorization needs, return format, pagination, or whether this is limited to the user's own listening history. This is minimal and does not fully convey the tool's behavior.

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

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

The description is a single sentence with no filler, front-loading the verb and resource. It is concise and efficiently conveys the core 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 read tool with one optional parameter, the description is adequate but not complete. It omits context about response structure, required Spotify scopes, and the fact that this returns the user's playback history. The lack of an output schema and annotations makes this more significant, but the simplicity of the operation keeps it at a minimum viable level.

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

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

The only parameter 'limit' is fully described in the schema with minimum/maximum values (1-50) and a clear description. Since schema coverage is 100%, the description need not add parameter details; 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?

The description uses the specific verb 'Get' with resource 'recently played tracks' and context 'on Spotify', clearly distinguishing from sibling tools like getNowPlaying (current track) and getTopTracks (top tracks over time). It states exactly what the tool does.

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

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

No guidance is provided on when to use this tool versus alternatives. The description does not mention any exclusions, prerequisites, or use cases beyond the basic action, so the agent must infer usage from the name and context.

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

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only says 'Get a list', which implies read-only behavior, but it does not mention pagination, authentication, or what happens if there are no saved tracks. Minimal behavioral context is added beyond the verb itself.

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

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

The description is a single sentence of 11 words, extremely concise and front-loaded with the action and object. It contains no filler, repetition, or unnecessary detail.

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 read tool with two optional numeric parameters, the description is adequate but lacks behavioral nuances such as pagination behavior and output structure. Since there is no output schema and no annotations, additional context about the returned list or pagination would make it more 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?

The input schema fully describes both parameters (limit and offset) with clear descriptions and constraints, achieving 100% schema description coverage. The description adds no additional parameter semantics, so the 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 clearly states the verb 'Get' and the specific resource 'tracks saved in the user's 'Liked Songs' library', which unambiguously distinguishes it from sibling tools like getAlbumTracks or getPlaylistTracks. It immediately conveys the tool's function without any ambiguity.

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

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

The description provides clear context by identifying the 'Liked Songs' library, making it easy to infer when this tool should be used instead of other track-retrieval tools. However, it does not explicitly mention exclusions or alternative tools, lacking the 'when-not' guidance that would push it to a 5.

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

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

No annotations provided, so description carries full burden. It fails to explain how the optional deviceId interacts with 'active device', or what happens if no device is active or playback is already paused. Auth requirements and error behavior are also undisclosed.

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?

Single sentence, front-loaded, and exactly as concise as needed. Every word earns its place.

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 pause tool, the description is minimal but sufficient at a basic level. However, it lacks guidance on device selection, idempotent behavior, and return values, which would be valuable for an agent with no annotations.

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 deviceId with 'The Spotify device ID to pause playback on' (100% coverage). Description adds little beyond that, and the phrase 'active device' may conflict with specifying a deviceId. No added clarity on when to provide the parameter.

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 states a specific verb ('Pause') and resource ('Spotify playback on the active device'), clearly distinguishing it from sibling tools like resumePlayback, playMusic, and skipToNext. No ambiguity.

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?

Usage is implied by the tool name and description: pause when wanting to stop playback. However, no explicit when-to-use guidance or alternatives are mentioned, leaving the agent to infer the context from sibling names.

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

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

No annotations exist, so the description must disclose side effects, requirements (like active device), and behavior such as replacing current queue. It only states the action, leaving the agent to guess about deviceId handling, error conditions, or return values.

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?

A single, to-the-point sentence. It's efficient but lacks additional context that could aid selection; still, it doesn't waste 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?

With no output schema and no annotations, the description fails to convey essential behavioral details such as whether playback starts immediately, what happens without a deviceId, or the response format. Incomplete for a 4-param tool with optional interactions.

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?

All four parameters are fully described in the schema, so the description adds no additional parameter semantics. It doesn't explain how id, uri, and type interrelate or which takes precedence.

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 uses a specific verb ('Start playing') and resource ('Spotify track, album, artist, or playlist'), clearly distinguishing from sibling playback controls like pause and skip. It accurately reflects the tool's function.

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

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

No explicit when-to-use or alternative guidance is provided. While the function is intuitive, it doesn't mention exclusions (e.g., when to use resume vs play) or prerequisites.

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

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

With no annotations, the description carries the full burden of disclosing behavioral traits. It does not mention failure conditions (e.g., no active device, nothing paused), side effects, or whether it requires an active device to be set. The description only states the action without additional context.

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

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

The description is a single sentence with no filler or repetition. It efficiently conveys the core action and target, earning a perfect score for conciseness.

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 one-parameter tool, the description covers the basic action and default behavior ('active device'). However, it lacks guidance on usage vs siblings and any note about error conditions, making it minimally complete but not comprehensive.

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

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

The schema provides a full description for the single optional deviceId parameter ('The Spotify device ID to resume playback on'), achieving 100% coverage. The description adds no extra meaning beyond this, so a 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 states the specific verb 'Resume' and resource 'Spotify playback' with the scope 'on the active device'. This clearly distinguishes it from sibling tools like playMusic (which starts playback) and pausePlayback (the opposite action).

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

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

No guidance is provided on when to use this tool versus alternatives such as playMusic or pausePlayback. The mention of 'active device' implies a prerequisite but does not explain when resumption is appropriate or what to do if no playback is paused.

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

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions the action ('save or remove') but lacks critical details: it doesn't specify authentication requirements, rate limits, whether changes are permanent or reversible, or what happens if album IDs are invalid. This is inadequate for a mutation tool with zero annotation coverage.

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

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

The description is a single, 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.

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

Given the tool's complexity as a mutation operation with no annotations and no output schema, the description is insufficient. It doesn't cover behavioral aspects like authentication needs, error handling, or response format, leaving significant gaps for an AI agent to understand how to use it correctly.

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

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

Schema description coverage is 100%, with clear descriptions for both parameters ('albumIds' and 'action'), including constraints like maxItems and enum values. The description adds no additional parameter semantics beyond what the schema provides, so it meets the baseline score of 3.

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 verb ('save or remove') and resource ('albums from the user's "Your Music" library'), making the purpose immediately understandable. However, it doesn't explicitly distinguish this tool from sibling tools like 'checkUsersSavedAlbums' or 'getAlbums', which are read-only operations, so it doesn't reach the highest score.

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 no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., user authentication), compare it to similar tools like 'addTracksToPlaylist' for saving tracks instead of albums, or specify scenarios where saving vs. removing is appropriate.

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

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

No annotations are provided, and the description offers no behavioral details beyond the basic search action. It does not disclose authentication needs, pagination, default limits, error handling, or return format, leaving the agent to infer these from the schema or context.

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

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

The description is a single sentence, front-loaded with the key verb 'Search' and the resource 'Spotify'. It is concise and free of unnecessary words, earning its place.

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 no output schema and no annotations, the description is too minimal. It does not explain how results are returned, how to handle no results, or how this integrates with sibling tools like getPlaylistTracks, leaving significant gaps for the agent.

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

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

The schema covers all parameters with descriptions (100% coverage), so the tool description does not need to add parameter information. However, the schema's limit description says '10-50' while the minimum is 1, and the tool description does not clarify this inconsistency.

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 uses the specific verb 'Search' and explicitly enumerates the item types (tracks, albums, artists, playlists). This clearly distinguishes it from sibling tools like getPlaylistTracks or playMusic, which focus on different actions.

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 implies the tool is for searching Spotify content but provides no explicit guidance on when to use it versus alternatives. It does not mention related workflows, exclusions, or prerequisites such as authentication via getAccessToken.

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

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It only states the action and doesn't mention prerequisites (e.g., active playback, deviceId optionality), side effects, or edge cases like an empty queue. This is a significant gap for a state-changing tool.

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

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

The description is a single sentence, highly concise, and front-loaded with the core action. No wasted words or 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 simple one-parameter tool, the description gives the essential purpose, but with no annotations or output schema, it lacks behavioral context such as what happens if no device is specified or whether playback must be active. It is minimally complete for selection but not fully informative.

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

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

The input schema already describes deviceId as 'The Spotify device ID to skip on' with full coverage. The description adds no additional parameter semantics, so the 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 a specific action ('Skip to the next track') on a specific resource ('current Spotify playback queue'). It distinguishes from sibling tools like skipToPrevious by explicitly indicating 'next'.

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 usage context is implied by the action and resource, but there is no explicit guidance on when to use this tool versus alternatives like skipToPrevious or pausePlayback. No exclusions 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.

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

No annotations are provided, so the description carries the full burden. It states the core action but does not disclose what happens at the start of the queue, whether a deviceId is required, or potential error conditions. The basic behavioral trait of changing playback is conveyed.

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

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

The description is a single, front-loaded sentence with no wasted words. It directly states the verb and resource without any tangential 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 simple tool with one optional parameter and no output schema, the description covers the primary action but lacks usage context, such as when to prefer this over 'skipToNext' or prerequisites. It is adequate but not thorough.

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

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

The schema already fully describes the single parameter (deviceId) with 100% coverage. The description does not add any additional meaning about the parameter, such as its optionality or behavior when omitted. Baseline 3 is appropriate since the schema handles it.

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 uses a specific verb ('Skip') with a clear resource ('previous track') and context ('in the current Spotify playback queue'). It clearly distinguishes from the sibling 'skipToNext' by specifying 'previous'.

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 implies when to use (when wanting to go backward in the queue) but does not explicitly mention alternatives like 'skipToNext' or any prerequisites such as an active playback session. No exclusions or when-not-to-use guidance provided.

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