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

The readOnlyHint annotation already establishes this as a read operation. The description adds substantive context by enumerating what it reports (API base, write-enablement, pacing, value ranges), which explains the tool's overall behavior beyond the bare annotation. No contradiction detected.

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

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

Two sentences, no filler. The primary purpose is front-loaded ('Reports...') and the secondary usage hint is appended concisely. 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 no-parameter introspection tool, the description is complete enough: it lists all reported aspects and a hint for a common use case. The lack of an output schema is not a significant gap since it's a capabilities report, but the exact format is unspecified, which is acceptable at this complexity.

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 tool has zero parameters, so the baseline is 4 per the rubric. The description correctly avoids any parameter explanation since none exist, and the schema (empty properties) already covers everything. No further semantics are needed.

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 ('Reports') and the exact content (API base, writes enabled, pacing, value ranges). It clearly distinguishes this tool from siblings like 'bandlab_whoami' (identity) and 'bandlab_list_songs' (queries) by focusing on server capabilities and limits.

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

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

Explicitly suggests a use case ('useful for diagnosing a refusal'), giving clear context for when to invoke it. It doesn't explicitly mention alternatives or when not to use it, but the purpose is well-scoped among siblings, so we credit the actionable hint.

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?

Annotations only say idempotentHint=false and destructiveHint=false; the description adds crucial behavior: dry runs show a diff without sending anything, and commits create a new revision rather than overwriting the original. This explains the non-idempotent, non-destructive nature far better than the hints alone and sets correct expectations for repeated calls.

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

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

Two sentences, front-loaded with the main action, then the two behavior-critical facts: dry run default and new-revision commit. No filler and no duplication of the schema.

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 complex 6-parameter tool with many op variants, the combination of description and fully-described schema is largely complete: the agent knows what action is taken, the safety model, and where parameters are described. The only real gap is that there is no output schema and the return/diff payload is only alluded to as 'shows the diff,' leaving result shape unspecified.

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

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

Schema coverage is 100%, and the schema itself documents every parameter, including dryRun, isPublic, revisionId, description, allowUnverifiedEffects, and the ops enum with rich descriptions like the volume automation envelope. The description does not attempt to repeat this, so it correctly leaves the schema to carry the load; no additional meaning is added beyond the dryRun/new-revision behavior.

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 opens with a clear verb and resource: 'Applies mix operations to a revision,' which tells the agent this is the mutation counterpart to read-only siblings like bandlab_get_mix and bandlab_list_revisions. It does not explicitly name an alternative or contrast itself, so it misses the top tier, but the purpose is 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?

The description gives operational context—dry run by default, dryRun=false to commit—and the revision-creation behavior, which tells the agent the safe way to preview changes. It never states when to choose this over bandlab_raw_request or bandlab_get_mix, nor gives exclusions, so usage guidance is 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.

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

Annotations already mark the operation readOnlyHint=true, so no safety disclosure is needed. The description adds useful behavioral context beyond that: it fetches a single revision and renders a compact text representation rather than raw JSON, which helps the agent anticipate output size and format.

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

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

Two sentences with no filler: the first states what the tool does and the output form, the second states when to use it. Everything 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 read-only tool with a fully documented schema, the description provides the essential context: it fetches one revision, what data is rendered, and the intended workflow position. Without an output schema, the concise mention of 'compact text' plus the listed musical elements is sufficient guidance.

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%, so the schema already documents revisionId and raw fully. The description adds no new parameter-level meaning beyond restating output fields, matching the baseline for a fully covered schema.

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

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

The description uses a specific verb ('Fetches') and resource ('one revision') and enumerates the rendered elements: tracks, levels, panning, effects, and regions. It also distinguishes itself from siblings like bandlab_list_revisions and bandlab_edit_mix by scoping to a single revision for read-before-edit purposes.

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?

'This is what you read before proposing an edit' gives clear situational context and implies the tool should precede bandlab_edit_mix. It does not enumerate exclusions or alternatives by name, but the intended workflow is evident.

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?

Beyond the readOnlyHint annotation, the description discloses meaningful behavioral context: the data source is harvested projects, there is no authoritative endpoint, and the server makes no guarantees for unlisted slugs. This warns the agent about a real reliability limitation, which is valuable beyond the annotation's safety hint.

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

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

Two tight sentences: the first states what the tool does, and the second carries the usage directive and caveat. No filler, no repetition of schema or annotation content.

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 filtered-list tool, this is complete: it names the output domain (slugs and parameters), gives usage timing, and flags the reliability caveat. It doesn't detail the exact return shape or pagination, but the tool is simple enough that this is a minor gap rather than a blocker.

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 fully documents the single optional query parameter with examples ('reverb', 'amp', 'drive'). The description adds no additional parameter-level detail, but the schema coverage is 100%, 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 opens with a specific verb and resource: 'Lists BandLab effect slugs and their parameters'. It also gives the data's provenance ('harvested from real published projects'), which clearly distinguishes this catalogue tool from the sibling tools that deal with songs, revisions, mixes, and capabilities.

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?

It explicitly instructs the agent to consult this tool 'before add_effect or set_effect_params' and explains why: BandLab has no effects endpoint, slugs are undocumented, and unlisted slugs cannot be vouched for. This is direct, actionable routing guidance rather than vague 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?

Annotations already declare readOnlyHint=true, and the description adds value beyond that by specifying ordering, verifying behavior against the live API, and clarifying that every save creates a revision. It does not describe pagination or return shape, but for a simple read tool this is adequate.

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

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

Two compact sentences with no fluff. The key scoping detail ('revision history', 'oldest first') is front-loaded, and the contextual note about BandLab's version model is placed after the main statement.

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 two-parameter read-only list tool, the description covers the essential semantics: what it lists, ordering, and why the revision history exists. A minor gap is the absence of output-format details, but no output schema exists and the title/description imply a revision list.

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 only 50%: songId is documented in the schema, but limit has no description beyond name/constraints. The tool description adds no parameter-level meaning, so it does not compensate for the undocumented limit 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 ('Lists') and a precise resource ('revision history of a song'), and adds a behavioral detail ('oldest first'). It is immediately distinguishable from siblings like bandlab_list_songs and bandlab_get_mix.

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 clearly frames when this tool is relevant by explaining that BandLab saves are revisions and calling this the 'undo history.' It does not explicitly name sibling alternatives, but the use case is evident and no conflicting alternative exists among the siblings.

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?

The annotations already declare readOnlyHint=true, and the description aligns with that by using 'Lists' (a read operation). Beyond annotations, it adds that only songs belonging to the authenticated user are returned and that the response includes song ids, which helps the agent understand scope and return value usage without contradicting the read-only hint.

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

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

The description is two sentences with no filler. The first sentence states the core purpose and scope, and the second provides a valuable workflow tip. 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?

Given the tool's simplicity (one optional parameter, read-only, no output schema), the description covers the essential context: what it lists, for whom, and how to use the result. It could mention pagination or response format more explicitly, but the lack of an output schema makes the mention of song ids sufficient for correct 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?

The schema has 100% description coverage for the single 'limit' parameter, including default, min, max, and meaning. The description does not add any parameter-specific information, so it earns 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 uses the specific verb 'Lists' with the resource 'songs belonging to the authenticated user', which precisely defines the tool's purpose. It also distinguishes itself from sibling tools by mentioning the follow-up use with bandlab_list_revisions, making it clear this is the song-listing entry point.

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 clearly states what the tool does and provides a workflow hint ('Use the returned song id with bandlab_list_revisions'), giving context for when to use it. It does not explicitly name alternatives or exclusions, but the main use case is clear and uniquely scoped to the authenticated user's songs.

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 supplied, the description carries the disclosure burden. It does disclose the write-permission gate and the undocumented nature of the API, which is useful. However, it does not describe response shape, error behavior, or side effects beyond method restrictions.

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

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

Three short sentences, each earning its place. The core purpose is front-loaded and the write restriction is stated clearly. No redundant or filler content.

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 description gives enough to start calling the tool and explains the key access constraint dropped by the schema. But since there is no output schema and no annotations, it should ideally warn that response formats are unknown or that arbitrary requests may behave unpredictably.

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 only 25%, so the description must compensate for the undocumented body and query parameters, but it does not explain them. It adds one useful parameter-specific constraint—GET vs. write methods—but leaves most parameter semantics to inference.

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 identifies this as an escape hatch for endpoints the server does not wrap, which distinguishes it from the dedicated sibling tools. It could be more explicit that it makes an arbitrary BandLab HTTP request, but 'this is how you explore it' conveys the main purpose well.

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?

It says the tool is for endpoints not yet wrapped, which implies using sibling tools for wrapped endpoints. It also gives a concrete condition: GET is always allowed, while other methods require writes to be enabled. This is practical guidance, though it does not explicitly name alternatives.

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?

The readOnlyHint annotation already covers the safety profile, and the description adds useful behavior beyond it: the tool verifies the session and returns authenticated profile data. It does not describe error behavior for an invalid session, but 'confirm the session works' strongly implies the outcome.

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

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

Two short sentences with no wasted words. The core return value is front-loaded, and the usage guidance is placed right after it. Every sentence 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 zero-parameter session-check tool with a readOnly annotation, the description is complete: it names the resource, the returned fields, the recommended call order, and the purpose. No output schema exists, but the description sufficiently covers the expected return values.

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 tool has zero parameters and 100% schema coverage, so there is no parameter burden for the description to carry. Baseline 4 is appropriate because no parameter semantics are needed.

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 ('Returns') with a clear resource ('authenticated BandLab profile') and names the returned fields (id, username, counters). It also tells the agent why this tool matters (getting the user id other tools need), which cleanly distinguishes it from the sibling tools like bandlab_list_songs or bandlab_capabilities.

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

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

The description explicitly says to call this tool first to confirm the session works and to obtain the user id needed by other tools. This gives clear contextual guidance, though it does not spell out when not to use it or name any alternative tool.

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