zas_send_direct_fallback

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

With no annotations present, the description carries the full burden and delivers: local encryption, storage of only the encrypted copy in Cloudflare R2, a 24-hour retention window, no consumption of owner space, download by the claiming device, and the behavioral shift that bytes now pass through storage. It also discloses owner visibility via the agent mark.

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?

Purpose and trigger are front-loaded and most sentences carry distinct information. A few clauses are conversational ('This stops being Directo', 'it is their choice') and could be tightened without losing meaning.

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?

Covers trigger, consent gate, encryption/storage mechanics, retention, and visibility for a tool with no annotations and no output schema. It omits what the call returns and what happens to the original failed job, which would round it out.

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 100% and the single job parameter is fully documented in the schema. The description's 'Pass the failed job's id' restates rather than extends that, 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 (deliver), resource (the same file), and a precise trigger condition (after a zas_send_direct job failed in flight), which distinguishes it cleanly from zas_send_direct and zas_receive_direct_fallback. An agent can identify the scenario without opening any schema.

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 an explicit trigger ('after a zas_send_direct job failed in flight') and a hard prerequisite ('Ask the owner before you use it; it is their choice'). It also names the originating tool whose failure selects this path, so the when-to-use decision is unambiguous.

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