list_blocks

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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior, so safety is covered. The description adds a small behavioral fact (the empty-args catalog-index behavior) but says nothing about pagination semantics, the cursor/response shape, or auth needs despite a read-heavy search surface.

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?

Three short sentences, front-loaded with the alias note and ending on the empty-args special case. Every sentence carries information, though the alias framing consumes the prominent first position.

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 14-parameter, zero-required search tool with no output schema, the description omits the response/pagination behavior and the design/session parameters (designId, pageId, slotId, componentId). It covers the catalog-index case but leaves the richer session-scoped usage unexplained.

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 all 14 parameters are already documented in the schema, including enums and pagination. The description's mention of 'query, role, family, or tag' overlaps with the schema rather than extending it, so the baseline 3 applies.

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 ('Search or list approved macro layout blocks') with filter dimensions. However, it opens by declaring itself an alias of search_macro_blocks, which muddies whether it is a distinct capability or a duplicate—an agent cannot tell from the description alone whether to prefer this tool or the sibling it mirrors.

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?

Explicitly documents the edge case 'When called with {}, returns the top-level macro block catalog index,' which is genuinely useful invocation guidance. It does not, however, say when to choose list_blocks over search_macro_blocks or get_macro_block, leaving the alias relationship ambiguous rather than routing the agent.

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