Read a draft's indicator sources

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

Annotations cover readOnlyHint and openWorldHint, but the description adds crucial behavioral details: the 64 KiB budget, the response size warning (~33k tokens), handling of duplicate filenames (first only, notes skipped count), and the note about truncation. This goes well beyond annotations and is fully transparent.

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?

While long, every sentence serves a purpose: main function, parameter behavior, edge cases, size warning, and alias. Information is front-loaded and logically ordered, with the critical warning in caps. Efficient and 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?

The description fully covers all invocation scenarios (with and without filename), duplicates, budget limits, and what the tool does not return. An output schema exists, so no need to detail return fields. Nothing essential is missing for correct 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 coverage is 0%, so the description bears full responsibility. It explains draftId as the id from list_drafts and filename as an exact-name filter with clear semantics (including the omission case). This adds meaning that the schema lacks entirely.

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 clearly states the verb (read) and resource (indicator source files a draft's EA embeds via #resource), and explicitly contrasts with get_draft. It distinguishes itself from siblings without ambiguity.

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 description explicitly explains when to pass filename (to read one attachment whole by exact name) and when to omit it (to get all sources up to a budget), and directs users to get_draft for the EA's own source. It also clarifies how to handle non-unique filenames.

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