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

Annotations declare readOnlyHint=false, and the description explains precisely why: the tool marks the submission as read by default, and it gives the escape hatch (mark_read=false to leave the is_read flag alone). This explains the mutation, its opt-out, and is consistent with idempotentHint=true (marking read twice is idempotent) and destructiveHint=false.

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?

Two sentences, front-loaded with the primary fetch purpose, then the side effect and its override. No filler; every clause 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?

With no output schema, the description compensates by enumerating the returned fields (name, email, message, every field value, schema at submission time) and discloses the read-marking side effect. An agent has everything needed to call 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 0%, so the description must carry the load; it does so for mark_read, explaining the default behavior and what false does—well beyond the bare boolean schema. submission_id is only implied by "by id" and not elaborated (e.g. UUID), leaving a small gap.

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?

States a specific verb and resource ("Fetch the full content of a form submission by id") and enumerates exactly what comes back (name, email, message, every field value, schema at submission time). The "by id" framing distinguishes it from list_submissions at a glance.

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?

Usage is implied: fetching a submission requires an id, and the mark_read default is explained. But there is no explicit guidance on when to choose this over siblings like list_submissions or draft_reply_to_submission, nor any precondition about obtaining an id first.

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