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

Annotations already declare destructiveHint=true, idempotentHint=false, and openWorldHint=true, so 'This can overwrite the selected wording' largely restates destructiveHint. The genuinely additive content is the 'style fanout and explicit batches' behavior, but it is not explained, and nothing is said about what a failed/partial batch leaves behind.

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 opening sentence is well front-loaded, but the closing sentence is jargon-heavy and oblique ('style fanout and explicit batches'), and 'For all text... in every intended print area' is ambiguous rather than efficient.

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 destructive mutation with a large, alias-riddled nested options object and no output schema. The description never explains which parameters are preferred over their aliases, what 'style fanout' means in practice, or how partial failures across areas are handled, leaving real gaps for a call of 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?

Schema description coverage is 100%, so the schema already documents most fields including the nested placement and text objects. The description adds only a targeting hint ('resolve targets from session state') and no guidance on the many aliases (elementId vs elementIds, allText vs areaIds, textColor vs textColour) that an agent must choose between.

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?

States a specific verb and resource ('replace existing text content or edit its style'), which cleanly separates it from add_text/create_design siblings without naming them. The scope is clear, though the distinction from add_text is only implied by the word 'existing'.

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?

'Resolve targets from session state' and the instruction to include every intended text object in every print area give some operational context, but there is no explicit statement of when to use this versus add_text or apply_design_batch, and no preconditions or exclusions.

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