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

Annotations already declare readOnly/idempotent/openWorld/non-destructive, so the safety profile is covered. The description usefully adds the 64 KB cap and the text-vs-base64 binary preview behavior, but the trailing custody/leverage/advice sentences are irrelevant boilerplate for a blob read.

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?

The first sentence is dense and front-loaded, but the two following sentences about non-custodial keys, spot-only, and education-only are entirely off-topic template padding for a read tool, roughly halving the signal-to-noise ratio.

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 rich annotations and no output schema, the description appropriately describes the return format (text or base64 preview, capped at 64 KB). It is close to complete, missing only error/availability behavior when the aggregator is unreachable.

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 0%, so the description must carry the load; it conveys the id lookup ('by id') and the byte cap ('max 64 KB'), which maps to max_bytes' maximum. It does not explain truncation behavior, the default of 8000, or the blob_id length bounds.

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+resource+scope: read a public Walrus mainnet blob by id via the public aggregator. This distinguishes it cleanly from siblings like walrus_store_guide (a guide) and build_walrus_register_tx (a write).

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?

It establishes context (public mainnet blobs via the aggregator) but never says when to prefer this tool over walrus_store_guide or other read tools, nor any prerequisites or exclusions. The agent must infer usage from the name alone.

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