kb_read_document

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

No annotations are provided, so the description carries the full burden, and it does disclose the single most important non-obvious trait: long documents are paged, with the instruction to re-call using `start_char` when `next_start_char` appears. It does not cover error behavior (missing/unreadable path) or confirmation that the call is a side-effect-free read, but the presence of an output schema lowers the need to describe return shape.

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 core behavior is front-loaded in the first sentence, with paging directly after it since that is the only behavioral surprise. The remaining lines are a compact param block with no filler; every sentence carries information an agent needs to page correctly.

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 three-parameter read tool with an output schema, the definition covers purpose, paging, and all parameter semantics adequately. The remaining omission is procedural context — how to discover a valid `relpath` and what happens on a bad path — which matters for first-time use but not for correct invocation once the path is known.

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 0%, so the description must compensate and does so fully: `relpath` is defined as volume-root relative with a concrete example (`02_Books/foo.pdf`), `max_chars` gains a valid range (1-50000) absent from the schema, and `start_char` is explained as the paging offset tied to the returned `next_start_char`. All three parameters gain meaning beyond the bare typed 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 and resource: returns the extracted plain text of one document, with the intended use ("for quoting/summarising") made explicit. It is distinguishable from sibling kb_search in practice, but the description never names or contrasts an alternative, so differentiation is inferred rather than stated.

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?

Usage is only implied by the parenthetical "for quoting/summarising" and by the paging instruction. There is no guidance on when to prefer this over kb_search, and crucially no hint that a `relpath` must first be obtained via kb_search or kb_list_tree — a real prerequisite gap for an agent that only knows a document name.

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