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

Annotations only declare the broad profile (readOnly=false, destructive=false, openWorld=false); the description goes well beyond them by spelling out the replace semantics: id-bearing blocks are merged, id-less blocks are added, and blocks absent from the list are DELETED. That deletion of unlisted blocks is exactly the kind of destructive sub-behavior an agent must know before calling, and it is disclosed explicitly. Note the mild tension with destructiveHint=false, though the slide entity itself is not destroyed, so this is disclosure rather than 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?

A single front-loaded sentence that leads with the verb and resource, then enumerates the mutable surface, then reserves the longest clause for the one non-obvious behavior (block-list replacement). No filler, no restatement of the title.

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 9-parameter mutation tool the critical ambiguity -- what happens to blocks omitted from `objects` -- is answered, and an output schema exists so return values need no explanation. Remaining gaps are secondary: no permission/auth context and no explicit routing to `edit_blocks` for partial edits.

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, and the description earns an extra point by supplying the merge/add/delete semantics of the `objects` array that the schema only hints at ("blocks bottom to top" with theme defaults). It still adds nothing for slug, slide_id, or the w/h vs bg vs background/fit distinction, which the schema handles alone.

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 ("Change a slide") and enumerates exactly which attributes are mutable: name, size, background colour/picture, and blocks. It is clear and self-contained, but it never distinguishes itself from the overlapping sibling `edit_blocks`, which an agent could easily confuse with the block-replacement arm of this tool.

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 only implied through the conditional "when 'objects' is given", which tells the agent that supplying objects triggers a full-list replacement. There is no guidance on when to prefer this tool over `edit_blocks` for partial block changes, nor any prerequisites or exclusions relative to `add_slide`, `update_presentation`, or `reorder_slides`.

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