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

Annotations already cover readOnlyHint, openWorldHint, and idempotentHint, so the safety profile is known. The description adds useful behavioral context beyond those annotations: atomic batch semantics, ordered output, and the specific card contents (identity, Hook, sealed claims with source addresses). Slightly more detail on what 'Atomic batch' guarantees could push it higher.

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 tight sentences with no filler. The core behavior is front-loaded, followed by the atomicity trait, then the sibling routing. Every sentence earns its place.

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?

The description fully equips an agent to select and invoke the tool: it specifies the input constraint (1-4 ids), the output composition, the batch behavior, and when to choose atlas_read instead. An output schema exists, so return-format details are not required in the description.

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 fully documents both ids and expected_revision. The description reinforces the 1-4 id limit but does not add new parameter-level meaning beyond the schema. Baseline 3 is appropriate because the schema carries the weight.

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 ('Read'), a precise resource ('canonical ids'), and the exact output shape ('one ordered Card per id: identity, Hook, and sealed claims with source addresses'). It explicitly differentiates from the sibling atlas_read by directing that tool to Section wording or a complete Node.

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?

The description provides clear routing guidance: use this tool for canonical-id card reads, and use atlas_read for Section wording or a complete Node. This gives an agent an explicit alternative and the condition that selects it, leaving little to inference.

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