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

No annotations exist, so the description carries the full burden. It discloses base64 encoding, text-based travel, size cost (roughly a third more), a size ceiling, and permission requirements. It doesn't mention error handling or explicit read-only status, but 'Read' implies non-mutating. This is strong transparency given the absence of annotations.

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 moderately long but every sentence adds value: purpose, encoding, cost warning, alternative, and permission. The core purpose is front-loaded, and the caveats follow naturally. No redundant filler.

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 read tool with no output schema, the description covers what the output looks like (base64), the cost implication, the alternative approach, and access requirements. It doesn't specify error behavior (e.g., missing file) but that's minor. Overall, an agent has enough to invoke it correctly.

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 100% with descriptions for both parameters. The description adds meaning by clarifying that 'filename' must match exactly what get_issue lists, and that 'key' is the issue key. It reinforces the parameter usage beyond the schema's basic definitions.

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 the resource 'one file attached to an issue', specifies base64 encoding, and distinguishes it from wiki attachments and the pm-files server. An agent can immediately understand what this tool does and how it differs from siblings.

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?

Explicitly explains when to use this tool (reading an attachment as text), and when not to (when size is a concern, use the pm-files server instead), and points to local_files_setup for connecting. It also clarifies the only prerequisite: permission to see the issue.

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