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

Annotations already establish the read-only, idempotent, non-destructive safety profile, and the description adds genuinely useful context: the fact/guidance/user kind taxonomy, that guidance text can be rewritten or disabled, and that some labels are locked by enabled tools. It doesn't mention pagination or auth requirements, but the added domain context is substantive.

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?

Front-loaded with the verb and resource, and every clause (kind taxonomy, cache phase, order, locks, md5) conveys information about the return payload rather than filler. It is a single dense run-on sentence, which slightly hurts readability but not wastefulness.

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?

With no output schema and only one param, the description carries the burden of explaining return contents and does so thoroughly, enumerating id, kind, cache phase, order, labels, and md5 defaults. It leaves only minor gaps such as pagination, which are low-impact for a read-only registry listing.

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?

There is a single optional in_workspace parameter whose meaning is fully documented in the schema (100% coverage), covering the workspace-override semantics. The description adds no parameter-level detail, so the baseline 3 for high schema coverage 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?

States a precise verb and resource ('List every block the platform assembles into agent system prompts') and even enumerates the returned fields, so the agent knows exactly what this produces. It doesn't, however, differentiate itself from the closest siblings prompts_blocks_get or prompts_blocks_preview, which an agent would need to tell apart.

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?

Gives explicit sequencing guidance ('Read this before prompts.blocks_update'), which clearly signals its role in the block-editing workflow. It does not name alternatives or state when NOT to use it versus get/preview, so it stops short of full routing guidance.

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