Remove a coupon from this patron's redemption list.
Cosmetic only — the coupon itself still exists at the operator,
and the patron can re-redeem the same code later while the
window allows. Free — requires proof of npub.
| Name | Required | Description | Default |
|---|---|---|---|
| npub | Yes | ||
| coupon_id | Yes | ||
| dpop_token | No |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description takes on full burden. It discloses key traits: cosmetic-only effect, re-redeemability, and authentication requirement. This goes beyond a simple action statement, though it omits idempotency or error handling details.
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 fluff. The most critical information (what it does, cosmetic nature, requirement) is front-loaded. Every sentence adds value.
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?
Given an output schema (handling return values), the description covers the effect and prerequisite for a simple mutation. It lacks mention of edge cases (e.g., coupon not in list) but is sufficient for typical use.
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 description must explain parameters. It only mentions npub as 'proof', ignoring coupon_id and dpop_token. This leaves significant gaps in understanding parameter purpose, especially for dpop_token.
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 clearly states the action ('Remove a coupon from this patron's redemption list') and specifies the resource and scope. It distinguishes itself from sibling tools like delete_coupon by emphasizing the cosmetic nature and that the coupon still exists.
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?
The description provides context ('cosmetic only', 'requires proof of npub') but does not explicitly guide when to use this tool versus alternatives like delete_coupon or redeem_coupon. The usage is implied, not explicit.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Each tool targets a distinct operation and domain (account, posts, coupons, credentials, scheduling, oracle, etc.), with clear differentiation even for similar-sounding tools like check_balance vs check_authority_balance or list_coupons vs list_my_coupons. There is no ambiguity.
All tools follow a consistent verb_noun snake_case pattern (e.g., create_post, delete_coupon, list_posts), with no mixing of styles. The excalibur_ prefix is uniform.
With 72 tools, the server far exceeds the typical well-scoped range (3–15). While the functionality is broad, the sheer number feels excessive for a single MCP server, leading to an extreme mismatch.
The tool surface covers the full lifecycle for core domains: CRUD for posts, snippets, coupons, credentials; complete flows for OAuth, npub proof, scheduling, notarization, and payments. No obvious gaps are present.