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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is known. The description adds the key behavioral context of 'Bulk support' (batched execution), which is valuable. It does not, however, explain return format (file contents as string? metadata?) or error behavior when a function_slug is not found.

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 concise and front-loaded: the first line states the core purpose, and the second line adds important bulk support information. No fluff, every sentence earns its place.

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 operation with three parameters and no output schema, the description covers the basics: what and batch capability. However, it lacks clarification on whether project_ids replaces project_id or is additional, what kind of file contents are returned (e.g., raw source, metadata), and potential size limits. Given the operation's simplicity, this is adequate but not complete.

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, but it only explains the 'bulk' aspect of the parameters. It does not elaborate on what project_id or function_slug represent beyond their names, nor does it clarify the relationship/usage of project_ids array, such as whether it is a shorthand for multiple projects or a full batch mode. The schema properties are bare, and the description adds minimal semantic value.

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 ('Retrieves file contents') and identifies the resource ('Edge Function in a Supabase project'), clearly indicating the tool's read operation. However, it does not explicitly differentiate from sibling tools like supabase_list_edge_functions (which lists functions) or supabase_deploy_edge_function (which deploys), though 'file contents' implies a fetch of source code.

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 implies usage for retrieving file contents of an Edge Function, and the 'Bulk support' note hints at when to use project_ids for batch operations. It does not explicitly state when to use this tool over alternatives (e.g., when you need code vs. a list), but the verb 'Retrieves' and resource context provide clarity.

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