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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so the safety profile is covered. The description adds only that content comes back as readable text with OCR flagged, and cites the underlying Fortnox endpoint GET /3/sie/{Type}; nothing about size, encoding, or error behavior beyond that.

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 short sentences with no padding, but the opening fragment "The SIE file." carries no information and the parenthetical list is confusing rather than front-loaded. It is terse without being well-structured.

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 6-parameter, filter-bearing read tool with a near-identical sibling (get_sie_file), the description omits any explanation of the filters, the Type values, and how it differs from its sibling. Annotations and the output schema cover safety and return shape, but the routing and parameter story remains incomplete.

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% and an output schema exists, so the schema carries the parameter documentation. The only extra signal is that Type appears as a path segment in /3/sie/{Type}, but the description says nothing about what values Type accepts or what the todate/fromdate/selection filters do.

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 fragment "The SIE file" names the resource but no verb; the second sentence ("Returns the text for you to read") supplies the action. The parenthetical "PDF text, OCR marked as such, or SIE" muddies rather than clarifies what is returned, and the sibling get_sie_file is never contrasted, so the agent must guess which of the two to call.

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?

There is no guidance on when to use this tool versus get_sie_file, get_fortnox_document, or read_fortnox_document, all of which plausibly retrieve document content. No prerequisites, no conditions, no exclusions are stated.

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