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

With no annotations at all, the description carries the full behavioral burden and does so: removeExisting destroys the other party's existing materials and private objects irreversibly, the tool defaults to a safe preview, and authorization limits are spelled out. An agent knows the destructive blast radius and the guardrail before calling.

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?

Dense but front-loaded: role and scope come first, then parameter semantics, then the confirmation workflow, then the prohibition. The semicolon-chained clauses are efficient, though the run-on style slightly hurts scanability.

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 seven-parameter, annotation-free mutation with no output schema, the description supplies authorization, per-user scoping, destructive-effect disclosure, the preview/consent handshake, and the self/manager exclusions. Nothing essential to calling it correctly is missing.

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, and it covers nearly every one of the seven parameters: blocked, removeExisting, preview, consent, previewHash (via the confirmation flow), and activityRef/userId (via 'verify activity and user'). Only format-level details (e.g., activityRef form, hash generation) are left to the schema.

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 names a concrete verb pair and resource: block (blocked=true) or restore (false) activity album uploads for a specific userId within one activity. That is specific enough to separate it from general account tools like block_user or ban_live_user, though it never names a sibling explicitly.

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?

It states the caller prerequisite (login/organizer), the scope restriction (only the specified userId for this activity), the hard exclusions (cannot target yourself or the activity manager), and a full preview-then-confirm workflow with the exact condition for the real call (same params + previewHash, consent=true, preview=false).

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