Add Process Timeline Slide (Step 1 Layout)

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

Annotations already declare readOnlyHint=false, idempotentHint=true and destructiveHint=false, so the write/idempotency profile is covered. The description adds genuinely useful design-side behavior (rounded card blocks, pulse connector vectors, >=24pt font floor, fixed presenter badge styling at 44pt Cyan #00B0F0), but it omits the persistence behavior: that a slide is appended to a .pptx at presentation_path and that a PNG thumbnail is exported by default. Those are the traits an agent most needs beyond the annotations.

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

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

It is a single front-loaded sentence with the purpose first, which is good. But it is heavily loaded with styling parentheticals and bilingual glosses ('rounded/oval number badges') that crowd out operational information, and it compresses a spec-sized amount of detail into a run-on line rather than separating layout from side effects.

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 10-parameter layout generator with full schema coverage, annotations and no output schema, the description covers the visual contract (steps, badges, connectors, typography, fixed presenter badge) pretty thoroughly. What is missing is operational context: where the slide lands, whether it appends to an existing deck, and what happens on export_thumbnail. Without an output schema, that gap keeps it short of a 5.

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 baseline is 3. The description reinforces a few semantics – the 3–5 step count, the presenter badge text/size/color tied to the 'presenter' param, and the >=24pt typography applied to step labels and descriptions – but adds little that the schema does not already document, and says nothing about non-visual params like design_id, palette_id or presentation_path.

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+resource: 'Dựng lộ trình tiến trình ngang (Roadmap 3–5 bước)' – i.e. it builds a horizontal process/roadmap slide, which an agent can distinguish from a KPI dashboard or SWOT matrix by the outcome described. However, it never names any sibling tool (canva_add_split_architecture, canva_add_tasteful_slide, etc.), so the differentiation is inferred from the artifact type rather than stated.

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?

There is no when-to-use guidance, no prerequisites, and no exclusions. With roughly 20 sibling canva_add_*/slide-building tools, the agent gets no routing signal for choosing this layout over e.g. canva_add_split_architecture or canva_execute_layout_script. The '3–5 bước' constraint is the only selection hint, and it duplicates the schema's minItems/maxItems.

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