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

Annotations already declare readOnlyHint and openWorldHint. Description adds significant behavioral context: fetches HTML+linked stylesheets, scans CSS for four categories, returns specific JSON structure including badge and disclosures. Discloses network I/O explicitly, aligning with openWorldHint. No contradiction.

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

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

Description is compact for the amount of detail, front-loading purpose and listing checks in a clear numbered list. Each sentence adds value. Slightly long but appropriate for the complexity.

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?

Despite no output schema, the description specifies the return structure ({ok, score, findings, summary, badge, disclosures, markdown}) and the condition for the badge. It covers limitations (runtime not audited) and network behavior. Complete for a single-parameter tool.

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 the single parameter (url) with 100% description. Description adds meaning by explaining the tool fetches the URL's HTML and linked stylesheets, implying the URL is the target page. This adds context beyond the schema's basic type and format.

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 specific verb 'audit' with resource 'live URL', lists four concrete CSS checks, and explicitly distinguishes from runtime motion auditors by disclosing 'Runtime motion... not audited (V2)'. This differentiates from sibling tools (catalog, compile, stats, validate) clearly.

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?

Implicitly states use case for static motion accessibility checks on live URLs. Highlights that runtime motion is not covered, guiding agents to avoid this tool for JS-based motion. Could be more explicit about when to prefer sibling tools, but the limitation is clearly stated.

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 tool readonly and non-open-world, so the core safety profile is clear. The description adds useful behavioral context about what the tool returns and its intended position as the first step in an authoring workflow. It does not hide any mutation or side-effect risk, and no destructiveness is implied.

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 front-loads the core purpose and contents, and the second sentence efficiently provides the required workflow context and points to sibling tools.

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 read-only catalog tool with no output schema, the description is complete: it states what is returned, when to call it, how to proceed afterward, and how the compile step is accessed. Nothing an agent needs to invoke it correctly is missing.

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 takes zero parameters, so there are no parameter semantics to clarify. The description compensates by explaining what the returned catalog includes and how to use it, meeting the baseline for a parameterless tool.

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: 'Returns the catalog of verified motion primitives...' and also explicitly includes 'authoring rules for writing a MotionSpec.' It distinguishes itself from the sibling validation, compilation, audit, and stats tools by describing exactly what this catalog tool produces.

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 direct workflow guidance: 'Call this FIRST, then write the spec yourself and validate it with motion_validate.' It also explains when motion_compile is appropriate ('runs in the CLI or with a key on the hosted endpoint'), which helps the agent choose the right tool in the sequence.

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 description adds significant context beyond annotations: it discloses deterministic compilation (idempotent), fail-closed validation, enforcement of prefers-reduced-motion, and a performance report. Annotations already indicate idempotentHint and readOnlyHint, but the description elaborates with concrete behaviors and outputs.

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, front-loaded with the key action and outputs. Every sentence adds value: the first covers validation, compilation, and features; the second covers determinism and return shape. No fluff.

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?

Despite no output schema, the description fully explains the return structure ({ok, js, css, report} or errors). It covers input, process, and output comprehensively for a compilation tool. Nested objects are described as MotionSpec JSON, and the behavioral details are complete.

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

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

Schema coverage is 100% with basic descriptions. The description enhances understanding by explaining that the spec is validated and compiled deterministically, and that specName is for artifact headers. This adds semantic value beyond the schema's minimal 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 that the tool validates (fail-closed) and compiles a MotionSpec into GSAP/CSS with deterministic output, specifying verb, resource, and output format. It distinguishes itself from siblings by focusing on compilation, while others like motion_validate and motion_audit handle 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?

The description implies when to use the tool (e.g., for production-ready code with reduced-motion fallbacks) but does not explicitly contrast with siblings or state when not to use it. The context is clear enough for an agent to infer, but lacks explicit exclusions or alternative recommendations.

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 declare readOnlyHint=true (safe read) and openWorldHint=false. The description adds meaningful behavioral context: it returns aggregated counts per outcome and identifies escalation clusters for catalog needs. This goes beyond the annotations without contradicting them.

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 extremely concise with two sentences and no unnecessary words. It is front-loaded with the core purpose ('Summary of routing/compile telemetry') and efficiently conveys the key output.

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 there is no output schema, the description adequately describes the return content (counts per outcome, escalation clusters). However, for a telemetry tool, it might be improved by clarifying the time period or data scope, though it is sufficient for basic 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 tool has zero parameters with 100% schema coverage (empty object). There are no parameters to document, so the description need not add parameter information. Baseline score of 4 is appropriate.

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

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

The description clearly states it provides a summary of routing/compile telemetry with counts per outcome and escalation clusters indicating catalog needs. However, it does not explicitly differentiate from sibling tools like motion_audit or motion_catalog, which could share similar 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?

No guidance is provided on when to use this tool versus alternatives. There is no mention of prerequisites, limitations, or comparison with sibling tools. The description only states what it does without any usage 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?

The description goes well beyond the readOnlyHint and openWorldHint annotations by disclosing fail-closed behavior, the exact return shape, and the non-obvious fact that warnings can be non-empty while ok=true. It also explains the accessibility implication, which is critical for correct agent 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 compact and front-loaded, with the core validation behavior stated first, followed by the return shape and the critical warning caveat. Every sentence earns its place, and the formatting highlights the most important behavioral nuance.

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 single-parameter, read-only validation tool with no output schema, the description fully covers what the tool does, when to use it, what it returns, and the key failure and warning semantics. An agent has sufficient information to select and invoke it correctly without additional 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?

Schema coverage for the single parameter is 100%, so the baseline is 3. The description adds meaningful semantics by clarifying that the spec parameter is a MotionSpec and by enumerating the validation dimensions applied to it, such as the primitive allow-list and injection rules, which the schema alone does not convey.

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 ('Checks') and a specific resource ('MotionSpec'), then enumerates exactly what it validates against: schema, primitive allow-list, parameter bounds, and injection rules. It clearly distinguishes itself from the sibling motion_compile by positioning validation as a pre-compile safety check.

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 'Use to pre-check a spec before compiling,' which gives clear guidance on when to call this tool. It also explains the important warning behavior so an agent knows this is the right tool for accessibility checks before compilation, though it does not explicitly name or exclude alternatives beyond the pre-compile framing.

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