Add accounts to your blocklist

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

Annotations already declare non-read-only, idempotent, non-destructive behavior, so the bar is lower. The description adds real context beyond that: entries are stored with an 'imported' marker and the skipping applies only to future dedup runs, not to enrich-known-list. It doesn't say whether duplicates are merged or errored, or how many were accepted.

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, no filler, with the primary effect stated first and the caveat and accepted formats following. Every clause carries operational information.

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 single-parameter mutation with no output schema and annotations covering the safety profile, the description supplies what an agent needs: what gets stored, what it affects, and the one behavioral exception. Return-value detail is unnecessary here.

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 carry the parameter burden and it largely does, enumerating accepted input forms (bare handle, @handle, instagram.com URL). It omits the schema's maxItems=5000 / non-empty-items constraints, which an agent batching a large list would want.

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?

It names a specific verb and resource ('Add Instagram handles ... to your dedup pool') and defines the operative state change ('as imported so future runs skip them'), which cleanly separates it from get_seen_accounts and reset_seen_accounts in the sibling list.

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 gives a clear use context and an important non-obvious exclusion — enrich-known-list still scans every handle it is given, so this blocklist is not universal. It stops short of naming the sibling tools (reset_seen_accounts, get_seen_accounts) as alternatives for the inverse operations.

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