Remove specific custom claim keys from Firebase Auth emulator users while preserving all other claims. Target one or more accounts by uid or uids, optionally within a tenant.
Remove the named custom claim keys from an Auth emulator user, keeping its other claims.
| Name | Required | Description | Default |
|---|---|---|---|
| uid | No | Account id | |
| keys | Yes | Claim names to remove | |
| uids | No | Several account ids (instead of uid) | |
| tenant | No | Tenant id; omit for a project-level user |
Changes observed during successful MCP inspections.
v0.2.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations at all, the description carries the full burden, and it does disclose the key merge behavior ('keeping its other claims'), which is genuinely useful for a mutation tool. It omits other behavioral facts an agent needs: whether removal is idempotent, what happens if a named key does not exist, whether the change persists in the emulator, and any auth/permission requirement.
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?
A single front-loaded sentence with the action, target, and the non-obvious preservation guarantee. No filler, no restating of the title, nothing that could be cut.
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 four-parameter mutation with no annotations and no output schema, the description covers the core contract but leaves the bulk (uids) path, tenant behavior, and error semantics to the schema. It is adequate as a minimum-viable definition but not complete for an agent operating without annotations.
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 all four parameters (uid, keys, uids, tenant) are already documented, making 3 the baseline. The description adds only 'custom claim keys' framing and implicitly confirms partial-merge semantics; it says nothing about the uid vs uids bulk alternative or tenant scoping beyond what the schema states.
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 specific verb ('Remove') and a specific resource ('named custom claim keys from an Auth emulator user'), and explicitly states the scoping behavior that other claims are preserved. It is clearly distinct from auth_set_claims by virtue of 'remove', though it never names that 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?
Usage is only implied: an agent can infer this is the deletion counterpart to auth_set_claims, but the description never says when to prefer this over setting claims to null, nor does it mention the bulk path (uids) or the tenant-scoping case. No when-not guidance is given.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.