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

The annotations already establish a safe, read-only operation. The description adds partial or chunked reading and an existing-source prerequisite, but provides no chunk size, offset default, continuation behavior, or return-shape context.

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?

A single short sentence front-loads the action and avoids filler. The phrase "in stretches" is ambiguous and less precise than wording such as "in chunks using a character offset," preventing top marks.

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 three-parameter read with full schema coverage and safety annotations, this is minimally sufficient to attempt a call. With no output schema and an offset-driven workflow, the lack of source-discovery guidance and chunk continuation details leaves notable gaps for reliable repeated invocation.

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 document_id, source_id, and offset are already documented and the baseline score applies. "In stretches" loosely reinforces offset-based reading, but the description adds no concrete defaults, invocation examples, or continuation semantics.

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—"Reads a source"—and narrows it to an already discovered source or uploaded file read "in stretches." It does not distinguish this tool from siblings such as deck_read_project_file, so it is clear but not fully differentiating.

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?

"Already found (or an uploaded file)" implies a prerequisite and a post-discovery or post-upload use case. It never identifies which tool supplies the source, when chunked reading is preferable, or when another reader should be used instead.

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