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

Annotations cover the write side (readOnlyHint=false, destructiveHint=false), and the description adds meaningful behavior: owner pays by default, encrypted items return locked bytes without a key, large items return download_url instead, and out-of-credit fallbacks (profile_key or x402 with a fee you pay). It doesn't state rate limits or idempotency behavior.

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-loads the core action and scope, then handles edge cases (encryption, large items, payment) in follow-up sentences. Efficient overall, though slightly dense with nested conditionals.

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?

No output schema, and the description compensates by describing the return shape (content text/base64, sha256, signed receipt, download_url). Covers the main retrieval paths and payment fallbacks, though permissions and error conditions aren't detailed.

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 three parameters already carry descriptions. The description adds context around key (unlocked vs locked bytes) and profile_key (only when owner is out of credit, or via header), but doesn't introduce new syntax or format beyond the schema.

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+resource: pick up an item with a ticket/link/relay code, and names the source siblings (anthill_store, anthill_share). It distinguishes retrieval from the many write-oriented siblings, though it doesn't explicitly contrast with anthill_delete or anthill_receipts.

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?

Implies usage ('no profile needed', 'pass the key to unlock', 'pass your own profile_key if the owner is out of credit'), which tells the agent when certain parameters are needed. However, it gives no explicit when-not-to-use or alternative-tool guidance.

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