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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description adds meaningful behavioral details beyond those: private-repo access behavior and rejection of binary files. It does not mention error cases or size limits, but it provides enough extra context to justify a score above baseline.

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 compact and front-loaded: the core purpose appears in the first sentence, followed by two useful behavioral clarifications. Every sentence earns its place without repetition or 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, the description covers the essential return behavior (text content, rejects binary), access considerations, and ref semantics. It does not describe output details like encoding or non-binary error cases, but these are not strict gaps for an agent invoking the tool.

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 the parameters are already fully documented. The description adds no new parameter semantics beyond the schema's existing statements about path, owner, repo, and ref. A baseline of 3 is appropriate because the schema carries the explanatory burden.

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: 'Read a single file from a repository at a given ref (branch / tag / commit).' It is clearly distinct from write/delete/list tools and explicitly limits scope to a single file. However, it does not differentiate itself from the very similarly named sibling gluecron_read_file, which leaves some selection 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 use case is implied: fetch file content at a known ref. It also gives useful context that private repos require authenticated access and that binary files are rejected. But it contains no explicit when/when-not guidance or mention of alternatives such as gluecron_read_file or gluecron_list_tree.

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