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

Annotations already cover readOnly/idempotent/openWorld, yet the description adds substantial behavioral context: login + organizer-role requirement, ID documents never decrypted, admin reveal requires an audit trail, registered phone masked to last-4, only self-filled phone shown in plaintext, and an instruction not to proactively repeat data. This is far beyond what annotations convey.

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?

Information-dense but front-loaded with an access tag and then constraints; each clause carries real meaning. The heavy semicolon chaining makes it slightly run-on, but there is little waste.

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 still explains what the response contains and how sensitive fields are masked (phone last-4, ID never decrypted), plus the audit requirement. For a read-only privacy-sensitive tool, an agent has everything needed to call and interpret 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 description coverage is 100%, so both slug and submissionId are already documented in the schema, including that submissionId comes from list_signup_submissions items[].id. The description adds the cross-event 404 behavior but no additional parameter syntax, so the baseline 3 applies.

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: read a single registrant's submission detail plus form contact info for a named event. It explicitly distinguishes itself from siblings, naming list_signup_submissions for locating and review_signup_submission for handling, so an agent can route without opening schemas.

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?

Gives an explicit precondition (only read when the person explicitly requests it), an access boundary (cross-event returns 404), and named alternatives for the locate and handle cases. When-to-use and which-sibling coverage is essentially complete.

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