ksef_upo_download

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

Annotations already declare readOnlyHint=true, and the description adds context by clarifying that UPO confirms system receipt and that an active session is required. It does not contradict annotations, though it does not reveal much beyond prerequisites and the document's purpose.

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 description is two short sentences with no filler. It front-loads the tool's core purpose, adds the UPO definition, and closes with the key prerequisite.

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 simple download tool with no output schema, the description provides purpose, domain context, and a prerequisite. It does not describe the downloaded file's format, but this is a minor gap given the low complexity and rich parameter schema.

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 already explains both parameters. The description adds no additional parameter-level detail beyond the general idea of downloading a UPO for an invoice in a session.

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 uses a specific verb and resource: 'Pobierz UPO' (download UPO) for an invoice in a KSeF session, and explains what UPO is. This clearly differentiates the tool from siblings like ksef_invoice_get or ksef_invoice_xml.

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 phrase 'Wymaga aktywnej sesji' gives a useful prerequisite, and the description implies the tool is used after an invoice has been submitted to obtain official receipt confirmation. However, it does not explicitly state when to use this tool over alternatives or when not to use it.

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