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

Annotations already flag destructiveHint=true and non-idempotent, so the bar is lower; the description still adds real value by disclosing partial-update semantics ('Only the fields you pass change') and the destructive mechanism ('pass "" to clear one'), which explains why the tool is marked destructive. It also warns of a side effect ('Turns remote config on') and of end-user impact (apps below the lowest version must update). Missing: what it returns and any plan/permission prerequisite.

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, with the destination URL and field scope front-loaded. The first sentence is dense but each clause maps to a real parameter group; trimming further would lose the clearing and enabling semantics.

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 an 11-parameter mutation with no output schema, the description covers what is changed, how partial updates behave, how to clear a value, and the enabling side effect — enough for an agent to call it correctly. Return-value explanation is not needed since no output schema is advertised and the effect is visible via app-config.json.

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%, so baseline is 3, but the description goes beyond the per-field schema blurbs by grouping the parameters into coherent concepts and explaining the relationship the schema does not ('the lowest supported and latest versions per platform (apps below the lowest must update)'). It also documents the cross-cutting convention that an empty string clears a field, which no single property description states.

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 and resource ('Change the remote config your app reads from https://{site}/app-config.json') and enumerates the exact fields it governs, which is far more specific than the sibling update_site or set_module. It never names a sibling to disambiguate against, but the resource is distinctive enough that confusion is unlikely.

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 implied by the field list (version gates, update message, maintenance mode, notice) plus the note that the call 'Turns remote config on', but there is no explicit when-to-use/when-not-to-use guidance and no named alternative such as update_site. An agent can infer the trigger but receives no exclusions.

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